cummins ISB, ISBe2, ISBe3, ISBe4, QSB4.5 Repair Manual

Troubleshooting and Repair Manual
ISB, ISBe2, ISBe3, ISBe4, QSB4.5, QSB5.9,
QSB6.7, ISC, QSC8.3, ISL, ISLe3, ISLe4, and
QSL9, CM850 Electronic Control System
Volume 3

Troubleshooting and Repair Manual
ISB, ISBe2, ISBe3, ISBe4, QSB4.5, QSB5.9, QSB6.7, ISC,
QSC8.3, ISL, ISLe3, ISLe4, and QSL9, CM850 Electronic Control
System
Volume 3

Copyright© 2014 Bulletin 4021416
Cummins Inc. Printed 01-APRIL-2014
All rights reserved

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Foreword

This manual provides instructions for troubleshooting and repairing this engine in the chassis. Component and
assembly rebuild procedures are provided in the engine shop manual. Refer to Section i - Introduction for instructions
on how to use this manual.

Read and follow all safety instructions. Refer to the WARNING in the General Safety Instructions in Section i ­Introduction.

The manual is organized to guide a service technician through the logical steps of identifying and correcting problems
related to the engine. This manual does not cover vehicle or equipment problems. Consult the vehicle or equipment
manufacturer for repair procedures.

A series of specific service manuals (for example: Shop, Specifications, and Alternative Repair) are available and can
be ordered by Contacting your local area Cummins Regional office. A Cummins Regional office listing is located in
Service Literature (Section L).

The repair procedures used in this manual are recommended by Cummins Inc. Some service procedures require the
use of special service tools. Use the correct tools as described.

Cummins Inc. encourages the user of this manual to report errors, omissions, and recommendations for improvement.
Please use the postage paid, pre-addressed Literature Survey Form in the back of this manual for communicating
your comments.

The specifications and rebuild information in this manual are based on the information in effect at the time of printing.
Cummins Inc. reserves the right to make any changes at any time without obligation. If differences are found between
your engine and the information in this manual, contact a Cummins Authorized Repair Location or call 1-800-DIESELS
(1-800-343-7357) toll free in the U.S. and Canada.

The latest technology and the highest quality components are used to manufacture Cummins engines. When
replacement parts are needed, we recommend using only genuine Cummins or ReCon® exchange parts.

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Table of Contents

Section

Introduction ........................................................................................................................................................ i

Troubleshooting Fault Codes (FC1669 - FC) ................................................................................................... TF

Back .................................................................................................................................................................... back

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ISB, ISBe2, ISBe3, ISBe4, QSB4 [...]
Section i - Introduction Page i-a

Section i - Introduction

Section Contents

Page

About the Manual .........................................................................................................................................................i-1

General Information.....................................................................................................................................................i-1

Acronyms and Abbreviations ...................................................................................................................................i-17

General Information...................................................................................................................................................i-17

General Cleaning Instructions ..................................................................................................................................i-12

Abrasive Pads and Abrasive Paper...........................................................................................................................i-12

Definition of Clean......................................................................................................................................................i-12

Fuel System...............................................................................................................................................................i-15

Gasket Surfaces........................................................................................................................................................ i-13

Plastic Bead Cleaning................................................................................................................................................i-14

Solvent and Acid Cleaning.........................................................................................................................................i-13

Steam Cleaning......................................................................................................................................................... i-14

General Repair Instructions ......................................................................................................................................i-10

General Information...................................................................................................................................................i-10

Welding on a Vehicle with an Electronic Controlled Fuel System..............................................................................i-11

General Safety Instructions ........................................................................................................................................i-8

Important Safety Notice...............................................................................................................................................i-8

How to Use the Manual ................................................................................................................................................i-2

General Information.....................................................................................................................................................i-2

Illustrations ...................................................................................................................................................................i-7

General Information.....................................................................................................................................................i-7

Symbols ........................................................................................................................................................................i-3

General Information.....................................................................................................................................................i-3

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Page i-b Section i - Introduction

This Page Left Intentionally Blank

ISB, ISBe2, ISBe3, ISBe4, QSB4 [...] About the Manual
Section i - Introduction Page i-1

About the Manual

General Information

This Troubleshooting and Repair Manual is intended to aid in determining the cause of engine related problems and to
provide recommended repair procedures.

The manual is divided into sections. Each section is equivalent to a group used in Cummins' filmcard system. Some
sections contain reference numbers and procedure numbers. Reference numbers provide general information,
specifications, diagrams, and service tools where applicable. Procedure numbers are used to identify and reference
specific repair procedures for correcting the problem.

This manual does not contain fuel systems electronic troubleshooting. Use the troubleshooting trees in this manual, if
there are no electronic fault codes.

This manual is designed so the troubleshooting trees are used to locate the cause of an engine problem. The
troubleshooting trees then direct the user to the correct repair procedure. The repair procedures within a section are in
numerical order. However, the repair steps within a given procedure are organized in the order the repair must be
performed regardless of the numerical order of the steps. The user must use the contents pages or the index at the
back of the manual to locate specific topics when not using the troubleshooting trees.

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How to Use the Manual ISB, ISBe2, ISBe3, ISBe4, QSB4 [...]
Page i-2 Section i - Introduction

How to Use the Manual

General Information

This manual is organized to provide an easy flow from problem identification to problem correction.

A list of troubleshooting symptoms containing the most common problems is in the Troubleshooting Symptoms,
Section (TS). The manual is designed to use the Troubleshooting Symptoms as a guide to locating the problem and
directing the end user to the correct procedure for making the repair. Complete the following steps to locate and
correct the problem.

1 Locate the symptom on the Section Contents pages of Section TS.

• Reference to the page number where the Troubleshooting Symptom Tree is found is made to the right of the
symptom tree title.

2 The left column of boxes in the Troubleshooting Symptom Charts indicates a probable cause of the problem,

starting at the top with the simplest and easiest to repair, and continuing downward to the most difficult.

• The right column of boxes provides a brief description of the corrective action with a reference number to the
correct procedure used to make the repair.

3 Locate the probable cause in the left column then turn to the procedure referenced in the right column.

4 The Troubleshooting Symptom Charts are based on the following assumptions:

• The components have been installed according to the manufacturer's specifications.

• The easiest repairs are done first.

• All generic solutions are designed for the most common applications and Original Equipment Manufacturer
(OEM).

Refer to the Original Equipment Manufacturer's service manual for their specifications.

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ISB, ISBe2, ISBe3, ISBe4, QSB4 [...] Symbols
Section i - Introduction Page i-3

Symbols

General Information

The symbols have been used in this manual to help communicate the intent of the instructions. When one of the
symbols appears, it conveys the meaning defined below.

NOTE: It is possible to have four symbols for each text and graphic combination.

WARNING
Serious personal injury or extensive property damage
can result if the warning instructions are not followed.

CAUTION
Minor personal injury can result or a part, and
assembly, or the engine can be damaged if the
caution instructions are not followed.

Indicates a REMOVAL or Dissassembly step.

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Symbols ISB, ISBe2, ISBe3, ISBe4, QSB4 [...]
Page i-4 Section i - Introduction

Indicates an INSTALLATION or ASSEMBLY step.

INSPECTION is required.

CLEAN the part or assembly.

PERFORM a mechanical or time MEASUREMENT.

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ISB, ISBe2, ISBe3, ISBe4, QSB4 [...] Symbols
Section i - Introduction Page i-5

LUBRICATE the part or assembly.

Indicates that a WRENCH or TOOL SIZE will be given.

TIGHTEN to a specific torque.

PERFORM an electrical MEASUREMENT.

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Symbols ISB, ISBe2, ISBe3, ISBe4, QSB4 [...]
Page i-6 Section i - Introduction

Refer to another location in this manual or another
publication for additional information.

The component weighs 23kg [50 lbs] or more. To reduce
the possibility of personal injury, use a hoist or get
assistance to lift the component.

To reduce the risk of high voltage
shock, always follow all warnings and
service instructions. Always assume
the vehicle and its high voltage system
are energized, even if the engine is not
running.

Approved high voltage insulated gloves
are required for this procedure.

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ISB, ISBe2, ISBe3, ISBe4, QSB4 [...] Illustrations
Section i - Introduction Page i-7

Illustrations

General Information

Some of the illustrations throughout this manual are
generic and will not look exactly like the engine or parts
used in your application. The illustrations can contain
symbols to indicate an action required and an acceptable
or not acceptable condition.

The illustrations are intended to show repair or
replacement procedures. The procedure will be the same
for all applications, although the illustration can differ.

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General Safety Instructions ISB, ISBe2, ISBe3, ISBe4, QSB4 [...]
Page i-8 Section i - Introduction

General Safety Instructions

Important Safety Notice

WARNING
Improper practices, carelessness, or ignoring the warnings can cause burns, cuts, mutilation, asphyxiation or
other personal injury or death.

Read and understand all of the safety precautions and warnings before performing any repair. This list contains the
general safety precautions that must be followed to provide personal safety. Special safety precautions are included
in the procedures when they apply.

• Work in an area surrounding the product that is dry, well lit, ventilated, free from clutter, loose tools, parts, ignition

sources and hazardous substances. Be aware of hazardous conditions that can exist.

• Always wear protective glasses and protective shoes when working.

• Rotating parts can cause cuts, mutilation or strangulation.

• Do not wear loose-fitting or torn clothing. Remove all jewelry when working.

• Disconnect the battery (negative [-] cable first) and discharge any capacitors before beginning any repair work.

Disconnect the air starting motor if equipped to prevent accidental engine starting. Put a "Do Not Operate" tag in
the operator's compartment or on the controls.

• Use ONLY the proper engine barring techniques for manually rotating the engine. Do not attempt to rotate the

crankshaft by pulling or prying on the fan. This practice can cause serious personal injury, property damage, or
damage to the fan blade(s) causing premature fan failure.

• If an engine has been operating and the coolant is hot, allow the engine to cool before slowly loosening the filler

cap to relieve the pressure from the cooling system.

• Always use blocks or proper stands to support the product before performing any service work. Do not work on

anything that is supported ONLY by lifting jacks or a hoist.

• Relieve all pressure in the air, oil, fuel, and cooling systems before any lines, fittings, or related items are removed

or disconnected. Be alert for possible pressure when disconnecting any device from a system that utilizes
pressure. Do not check for pressure leaks with your hand. High pressure oil or fuel can cause personal injury.

• To reduce the possibility of suffocation and frostbite, wear protective clothing and ONLY disconnect liquid

refrigerant (Freon) lines in a well ventilated area. To protect the environment, liquid refrigerant systems must be
properly emptied and filled using equipment that prevents the release of refrigerant gas (fluorocarbons) into the
atmosphere. Federal law requires capturing and recycling refrigerant.

• To reduce the possibility of personal injury, use a hoist or get assistance when lifting components that weigh 23 kg

[50 lb] or more. Make sure all lifting devices such as chains, hooks, or slings are in good condition and are of the
correct capacity. Make sure hooks are positioned correctly. Always use a spreader bar when necessary. The lifting
hooks must not be side-loaded.

• Corrosion inhibitor, a component of SCA and lubricating oil, contains alkali. Do not get the substance in eyes.

Avoid prolonged or repeated contact with skin. Do not swallow internally. In case of contact, immediately wash
skin with soap and water. In case of contact, immediately flood eyes with large amounts of water for a minimum of
15 minutes. IMMEDIATELY CALL A PHYSICIAN. KEEP OUT OF REACH OF CHILDREN.

• Naptha and Methyl Ethyl Ketone (MEK) are flammable materials and must be used with caution. Follow the

manufacturer's instructions to provide complete safety when using these materials. KEEP OUT OF REACH OF
CHILDREN.

• To reduce the possibility of burns, be alert for hot parts on products that have just been turned off, exhaust gas

flow, and hot fluids in lines, tubes, and compartments.

• Always use tools that are in good condition. Make sure you understand how to use the tools before performing any

service work. Use ONLY genuine Cummins® or Cummins ReCon® replacement parts.

• Always use the same fastener part number (or equivalent) when replacing fasteners. Do not use a fastener of

lesser quality if replacements are necessary.

• When necessary, the removal and replacement of any guards covering rotating components, drives, and/or belts

should only be carried out be a trained technician. Before removing any guards the engine must be turned off and
any starting mechanisms must be isolated. All fasteners must be replaced on re-fitting the guards.

• Do not perform any repair when fatigued or after consuming alcohol or drugs that can impair your functioning.

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ISB, ISBe2, ISBe3, ISBe4, QSB4 [...] General Safety Instructions
Section i - Introduction Page i-9

• Some state and federal agencies in the United States of America have determined that used engine oil can be
carcinogenic and can cause reproductive toxicity. Avoid inhalation of vapors, ingestion, and prolonged contact with
used engine oil.

• Do not connect the jumper starting or battery charging cables to any ignition or governor control wiring. This can
cause electrical damage to the ignition or governor.

• Always torque fasteners and fuel connections to the required specifications. Overtightening or undertightening can
allow leakage. This is critical to the natural gas and liquefied petroleum gas fuel and air systems.

• Always test for fuel leaks as instructed, as odorant can fade.

• Close the manual fuel valves prior to performing maintenance and repairs, and when storing the vehicle inside.

• Coolant is toxic. If not reused, dispose of in accordance with local environmental regulations.

• The catalyst reagent contains urea. Do not get the substance in your eyes. In case of contact, immediately flood
eyes with large amounts of water for a minimum of 15 minutes. Avoid prolonged contact with skin. In case of
contact, immediately wash skin with soap and water. Do not swallow internally. In the event the catalyst reagent is
ingested, contact a physician immediately.

• The catalyst substrate contains Vanadium Pentoxide. Vanadium Pentoxide has been determined by the State of
California to cause cancer. Always wear protective gloves and eye protection when handling the catalyst assembly.
Do not get the catalyst material in your eyes. In Case of contact, immediately flood eyes with large amounts of
water for a minimum of 15 minutes. Avoid prolonged contact with skin. In case of contact, immediately wash skin
with soap and water.

• The Catalyst substrate contains Vanadium Pentoxide. Vanadium Pentoxide has been determined by the State of
California to cause cancer. In the event the catalyst is being replaced, dispose of in accordance with local
regulations.

• California Proposition 65 Warning - Diesel engine exhaust and some of its constituents are known to the State of
California to cause cancer, birth defects, and other reproductive harm.

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General Repair Instructions ISB, ISBe2, ISBe3, ISBe4, QSB4 [...]
Page i-10 Section i - Introduction

General Repair Instructions

General Information

This system incorporates the latest technology at the time it was manufactured; yet, it is designed to be repaired using
normal repair practices performed to quality standards.

WARNING
Cummins Inc. does not recommend or authorize any modifications or repairs to components except for those
detailed in Cummins Service Information. In particular, unauthorized repair to safety-related components can
cause personal injury or death. Below is a partial listing of components classified as safety-related:

1 Air Compressor

2 Air Controls

3 Air Shutoff Assemblies

4 Balance Weights

5 Cooling Fan

6 Fan Hub Assembly

7 Fan Mounting Bracket(s)

8 Fan Mounting Capscrews

9 Fan Hub Spindle

10 Flywheel

11 Flywheel Crankshaft Adapter

12 Flywheel Mounting Capscrews

13 Fuel Shutoff Assemblies

14 Fuel Supply Tubes

15 Lifting Brackets

16 Throttle Controls

17 Turbocharger Compressor Casing

18 Turbocharger Oil Drain Line(s)

19 Turbocharger Oil Supply Line(s)

20 Turbocharger Turbine Casing

21 Vibration Damper Mounting Capscrews

22 Manual Service Disconnect

23 High Voltage Interlock Loop

24 High Voltage Connectors/Connections and Harnesses

25 High Voltage Battery System

26 Power Inverter

27 Generator Motor

28 Clutch Pressure Plate

• Follow all safety instructions noted in the procedures

• Follow the manufacturer's recommendations for cleaning solvents and other substances used during repairs. Some

solvents have been identified by government agencies as toxic or carcinogenic. Avoid excessive breathing,
ingestion and contact with such substances. Always use good safety practices with tools and equipment

• Provide a clean environment and follow the cleaning instructions specified in the procedures

• All components must be kept clean during any repair. Contamination of the components will cause premature

wear.

• Perform the inspections specified in the procedures

• Replace all components or assemblies which are damaged or worn beyond the specifications

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ISB, ISBe2, ISBe3, ISBe4, QSB4 [...] General Repair Instructions
Section i - Introduction Page i-11

• Use genuine Cummins new or ReCon® service parts and assemblies

- The assembly instructions have been written to use again as many components and assemblies as possible.
When it is necessary to replace a component or assembly, the procedure is based on the use of new Cummins or
Cummins ReCon® components. All of the repair services described in this manual are available from all Cummins
Distributors and most Dealer locations.

• Follow the specified disassembly and assembly procedures to reduce the possibility of damage to the components

Welding on a Vehicle with an Electronic Controlled Fuel System

CAUTION
Disconnect both the positive (+) and negative (-) battery cables from the battery before welding on the vehicle.
Attach the welder ground cable no more than 0.61 meters [2 feet] from the part being welded. Do not connect
the ground clamp of the welder to any of the sensors, wiring harness, electronic control units or the
components. Direct welding of any electronic components must not be attempted. Sensors, wiring harness,
and electronic control unit should be removed if nearby welding will expose these components to
temperatures beyond normal operation. Additionally, all electronic control unit connectors must be
disconnected

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Page i-12 Section i - Introduction

General Cleaning Instructions

Definition of Clean

Parts must be free of debris that can contaminate any engine system. This does not necessarily mean they have to
appear as new.

Sanding gasket surfaces until the factory machining marks are disturbed adds no value and is often harmful to forming
a seal. It is important to maintain surface finish and flatness tolerances to form a quality sealing surface. Gaskets are
designed to fill small voids in the specified surface finish.

Sanding gasket surfaces where edge-molded gaskets are used is most often unnecessary. Edge-molded gaskets are
those metal carriers with sealing material bonded to the edges of the gasket to seal while the metal portion forms a
metal to metal joint for stability. Any of the small amounts of sealing material that can stick to the parts are better
removed with a blunt-edged scraper on the spots rather than spending time polishing the whole surface with an air
sander or disc.

For those gaskets that do not have the edge molding, nearly all have a material that contains release agents to
prevent sticking. Certainly this is not to say that some gaskets are not difficult to remove because the gasket has
been in place a long time, has been overheated or the purpose of the release agent has been defeated by the
application of some sealant. The object however is just to remove the gasket without damaging the surfaces of the
mating parts without contaminating the engine (don't let the little bits fall where they can not be removed).

Bead blasting piston crowns until the dark stain is removed is unnecessary. All that is required is to remove the carbon
build-up above the top ring and in the ring grooves. There is more information on bead blasting and piston cleaning
later in this document.

Cummins Inc. does not recommend sanding or grinding the carbon ring at the top of cylinder liners until clean metal is
visible. The liner will be ruined and any signs of a problem at the top ring reversal point (like a dust-out) will be
destroyed. It is necessary to remove the carbon ring to provide for easier removal of the piston assembly. A medium
bristle, high quality, steel wire wheel that is rated above the rpm of the power tool being used will be just as quick and
there will be less damage. Yes, one must look carefully for broken wires after the piston is removed but the wires are
more visible and can be attracted by a magnet.

Oil on parts that have been removed from the engine will attract dirt in the air. The dirt will adhere to the oil. If possible,
leave the old oil on the part until it is ready to be cleaned, inspected and installed, and then clean it off along with any
attracted dirt. If the part is cleaned then left exposed it can have to be cleaned again before installation. Make sure
parts are lubricated with clean oil before installation. They do not need to be oiled all over but do need oil between
moving parts (or a good lube system priming process conducted before cranking the engine).

Bead blasting parts to remove exterior paint is also usually unnecessary. The part will most likely be painted again so
all that needs happen is remove any loose paint.

Abrasive Pads and Abrasive Paper

The keyword here is "abrasive". There is no part of an engine designed to withstand abrasion. That is they are all
supposed to lock together or slide across each other. Abrasives and dirt particles will degrade both functions.

WARNING
Abrasive material must be kept out of or removed from oil passages and parts wear points. Abrasive material
in oil passages can cause bearing and bushing failures that can progress to major component damage
beyond reuse. This is particularly true of main and rod bearings.

Cummins Inc. does not recommend the use of emery cloth or sand paper on any part of an assembled engine or
component including but not limited to removing the carbon ridge from cylinder liners or to clean block decks or
counterbores.

Great care must be taken when using abrasive products to clean engine parts, particularly on partially assembled
engines. Abrasive cleaning products come in many forms and sizes. All of them contain aluminum oxide particles,
silicon carbide, or sand or some other similar hard material. These particles are harder than most of the parts in the
engine. Since they are harder, if they are pressed against softer material they will either damage the material or
become embedded in it. These materials fall off the holding media as the product is used. If the products are used with
power equipment the particles are thrown about the engine. If the particles fall between two moving parts, damage to
the moving parts is likely.

If particles that are smaller than the clearance between the parts while they are at rest (engine stopped), but larger
than the running clearance then damage will occur when the parts move relative to each other (engine started). While
the engine is running and there is oil pressure, particles that are smaller than the bearing clearance are likely to pass
between the parts without damage and be trapped in the oil filter. However, particles larger than the bearing clearance
will remove material from one part and can become embedded in one of the parts. Once embedded in one part it will

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ISB, ISBe2, ISBe3, ISBe4, QSB4 [...] General Cleaning Instructions
Section i - Introduction Page i-13

abrade the other part until contact is no longer being made between the two parts. If the damage sufficiently degrades
the oil film, the two parts will come into contact resulting in early wear-out or failure from lack of effective lubrication.

Abrasive particles can fly about during cleaning it is very important to block these particles from entering the engine as
much as possible. This is particularly true of lubricating oil ports and oil drilling holes, especially those located
downstream of the lubricating oil filters. Plug the holes instead of trying to blow the abrasive particles and debris with
compressed air because the debris is often simply blown further into the oil drilling.

All old gasket material must be removed from the parts gasket surfaces. However, it is not necessary to clean and
polish the gasket surface until the machining marks are erased. Excessive sanding or buffing can damage the gasket
surface. Many newer gaskets are of the edge molded type (a steel carrier with a sealing member bonded to the steel).
What little sealing material that can adhere is best removed with a blunt-edged scraper or putty knife. Cleaning gasket
surfaces where an edge-molded gasket is used with abrasive pads or paper is usually a waste of time.

WARNING
Excessive sanding or grinding the carbon ring from the top of the cylinder liners can damage the liner beyond
reuse. The surface finish will be damaged and abrasive particles can be forced into the liner material which
can cause early cylinder wear-out or piston ring failures.

Tape off or plug all openings to any component interior before using abrasive pads or wire brushes. If really necessary
because of time to use a power tool with abrasive pads, tape the oil drillings closed or use plug and clean as much of
the surface as possible with the tool but clean around the oil hole/opening by hand so as to prevent contamination of
the drilling. Then remove the tape or plug and clean the remaining area carefully and without the tool. DO NOT use
compressed air to blow the debris out of oil drilling on an assembled engine! More likely than not, the debris can be
blown further into the drilling. Using compressed air is fine if both ends of the drilling are open but that is rarely the
case when dealing with an assembled engine.

Gasket Surfaces

The object of cleaning gasket surfaces is to remove any gasket material, not refinish the gasket surface of the part.

Cummins Inc. does not recommend any specific brand of liquid gasket remover. If a liquid gasket remover is used,
check the directions to make sure the material being cleaned will not be harmed.

Air powered gasket scrapers can save time but care must be taken to not damage the surface. The angled part of the
scraper must be against the gasket surface to prevent the blade from digging into the surface. Using air powered
gasket scrapers on parts made of soft materials takes skill and care to prevent damage.

Do not scrape or brush across the gasket surface if at all possible.

Solvent and Acid Cleaning

Several solvent and acid-type cleaners can be used to clean the disassembled engine parts (other than pistons. See
Below). Experience has shown that the best results can be obtained using a cleaner that can be heated to 90° to 95°
Celsius (180° to 200° Fahrenheit). Kerosene emulsion based cleaners have different temperature specifications, see
below. A cleaning tank that provides a constant mixing and filtering of the cleaning solution will give the best results.
Cummins Inc. does not recommend any specific cleaners. Always follow the cleaner manufacturer's instructions.
Remove all the gasket material, o-rings, and the deposits of sludge, carbon, etc., with a wire brush or scraper before
putting the parts in a cleaning tank. Be careful not to damage any gasket surfaces. When possible, steam clean the
parts before putting them in the cleaning tank.

WARNING
When using solvents, acids, or alkaline materials for cleaning, follow the manufacturers recommendations for
use. Wear goggles and protective clothing to reduce the possibility of personal injury.

Experience has shown that kerosene emulsion based cleaners perform the best to clean pistons. These cleaners
should not be heated to temperature in excess of 77°C (170°F). The solution begins to break down at temperatures in
excess of 82°C (180°F) and will be less effective.

Do not use solutions composed mainly of chlorinated hydrocarbons with cresols, phenols and/or cresylic components.
They often do not do a good job of removing deposits from the ring groove and are costly to dispose of properly.

Solutions with a pH above approximately 9.5 will cause aluminum to turn black; therefore do not use high alkaline
solutions.

Chemicals with a pH above 7.0 are considered alkaline and those below 7.0 are acidic. As you move further away
from the neutral 7.0, the chemicals become highly alkaline or highly acidic.

Remove all the gasket material, o-rings, and the deposits of sludge, carbon, etc., with a wire brush or scraper before
putting the parts in a cleaning tank. Be careful to not damage any gasket surfaces. When possible use hot high

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General Cleaning Instructions ISB, ISBe2, ISBe3, ISBe4, QSB4 [...]
Page i-14 Section i - Introduction

pressure water or steam clean the parts before putting them in the cleaning tank. Removing the heaviest dirt before
placing in the tank will allow the cleaner to work more effectively and the cleaning agent will last longer.

Rinse all the parts in hot water after cleaning. Dry completely with compressed air. Blow the rinse water from all the
capscrew holes and the oil drillings.

If the parts are not to be used immediately after cleaning, dip them in a suitable rust proofing compound. The rust
proofing compound must be removed from the parts before assembly or installation on the engine.

Steam Cleaning

Steam cleaning can be used to remove all types of dirt that can contaminate the cleaning tank. It is a good method for
cleaning the oil drillings and coolant passages

WARNING
When using a steam cleaner, wear safety glasses or a face shield, as well as protective clothing. Hot steam
can cause serious personal injury.

Do not steam clean the following components:

• Electrical Components

• Wiring Harnesses

• Belts and Hoses

• Bearings (ball or taper roller)

• Electronic Control Module (ECM)

• ECM Connectors

• Capacitive Coil Driver Module (CCD)

• Ignition Coils and Leads

• NOx Sensor

• Fuel Control Valve

• Throttle Driver and Actuator.

Plastic Bead Cleaning

Cummins Inc. does not recommend the use of glass bead blast or walnut shell media on any engine part. Cummins
Inc. recommends using only plastic bead media, Part Number 3822735 or equivalent on any engine part. Never use
sand as a blast media to clean engine parts. Glass and walnut shell media when not used to the media
manufacturer's recommendations can cause excess dust and can embed in engine parts that can result in premature
failure of components through abrasive wear.

Plastic bead cleaning can be used on many engine components to remove carbon deposits. The cleaning process is
controlled by the use of plastic beads, the operating pressure and cleaning time.

CAUTION
Do not use bead blasting cleaning methods on aluminum pistons skirts or the pin bores in any piston, piston
skirt or piston crown. Small particles of the media will embed in the aluminum or other soft metal and result in
premature wear of the cylinder liner, piston rings, pins and pin bores. Valves, turbocharger shafts, etc., can
also be damaged. Follow the cleaning directions listed in the procedures.

CAUTION
Do not contaminate wash tanks and tank type solvent cleaners with the foreign material and plastic beads.
Remove the foreign material and plastic beads with compressed air, hot high pressure water or steam before
placing them in tanks or cleaners. The foreign material and plastic beads can contaminate the tank and any
other engine parts cleaned in the tank. Contaminated parts may cause failures from abrasive wear.

Plastic bead blasting media, Part Number 3822735, can be used to clean all piston ring grooves. Do not sure any
bead blasting media on piston pin bores or aluminum skirts.

Follow the equipment manufacturer's cleaning instructions. Make sure to adjust the air pressure in the blasting
machine to the bead manufacturer's recommendations. Turning up the pressure can move material on the part and
cause the plastic bead media to wear out more quickly. The following guidelines can be used to adapt to
manufacturer's instructions:

1 Bead size: U.S. size Number 16 — 20 for piston cleaning with plastic bead media, Part Number 3822735

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ISB, ISBe2, ISBe3, ISBe4, QSB4 [...] General Cleaning Instructions
Section i - Introduction Page i-15

2 Operating Pressure — 270 kPa (40 psi) for piston cleaning. Pressure should not cause beads to break.

3 Steam clean or wash the parts with solvent to remove all of the foreign material and plastic beads after cleaning.

Rinse with hot water. Dry with compressed air.

CAUTION
The bead blasting operation must not disturb the metal surface. If the metal surface is disturbed the engine
can be damaged due to increased parts clearance or inadequate surface finish on parts that move against
other parts.

When cleaning pistons, it is not necessary to remove all the dark stain from the piston. All that is necessary is to
remove the carbon on the rim and in the ring grooves. This is best done by directing the blast across the part as
opposed to straight at the part. If the machining marks are disturbed by the blasting process, then the pressure is too
high or the blast is being held on one spot too long. The blast operation must not disturb the metal surface.

Walnut shell bead blast material is sometimes used to clean ferrous metals (iron and steel). Walnut shell blasting
produces a great amount of dust particularly when the pressure if the air pressure on the blasting machine is
increased above media manufacturer's recommendation. Cummins Inc. recommends not using walnut shell media to
clean engine parts due to the risk media embedment and subsequent contamination of the engine.

Cummins Inc. now recommends glass bead media NOT used to clean any engine parts. Glass media is too easily
embedded into the material particularly in soft materials and when air pressures greater than media manufacturer's
recommend are used. The glass is an abrasive so when it is in a moving part, that part is abrading all the parts in
contact with it. When higher pressures are used the media is broken and forms a dust of a very small size that floats
easily in the air. This dust is very hard to control in the shop, particularly if only compressed air (and not hot water) is
used to blow the media after it is removed from the blasting cabinet (blowing the part off inside the cabinet may
remove large accumulations but never removes all the media).

Bead blasting is best used on stubborn dirt/carbon build-up that has not been removed by first steam/higher pressure
washing then washing in a heated wash tank. This is particularly true of pistons. Steam and soak the pistons first then
use the plastic bead method to safely remove the carbon remaining in the grooves (instead of running the risk of
damaging the surface finish of the groove with a wire wheel or end of a broken piston ring. Make sure the parts are dry
and oil free before bead blasting to prevent clogging the return on the blasting machine.

Always direct the bead blaster nozzle "across" rather than directly at the part. This allows the bead to get under the
unwanted material. Keep the nozzle moving rather than hold on one place. Keeping the nozzle directed at one-place
too long causes the metal to heat up and be moved around. Remember that the spray is not just hitting the dirt or
carbon. If the machining marks on the piston groove or rim have been disturbed then there has not been enough
movement of the nozzle and/or the air pressure is too high.

Never bead blast valve stems. Tape or use a sleeve to protect the stems during bead blasting. Direct the nozzle
across the seat surface and radius rather than straight at them. The object is to remove any carbon build up and
continuing to blast to remove the stain is a waste of time.

Fuel System

When servicing any fuel system components, which can be exposed to potential contaminants, prior to disassembly,
clean the fittings, mounting hardware, and the area around the component to be removed. If the surrounding areas are
not cleaned, dirt or contaminants can be introduced into the fuel system.

The internal drillings of some injectors are extremely small and susceptible to plugging from contamination. Some fuel
injection systems can operate at very high pressures. High pressure fuel can convert simple particles of dirt and rust
into a highly abrasive contaminant that can damage the high pressure pumping components and fuel injectors.

Electrical contact cleaner can be used if steam cleaning tools are not available. Use electrical contact cleaner rather
than compressed air, to wash dirt and debris away from fuel system fittings. Diesel fuel on exposed fuel system parts
attracts airborne contaminants.

Choose lint free towels for fuel system work.

Cap and plug fuel lines, fittings, and ports whenever the fuel system is opened. Rust, dirt, and paint can enter the fuel
system whenever a fuel line or other component is loosened or removed from the engine. In many instances, a good
practice is to loosen a line or fitting to break the rust and paint loose, and then clean off the loosened material.

When removing fuel lines or fittings from a new or newly-painted engine, make sure to remove loose paint flakes/chips
that can be created when a wrench contacts painted line nuts or fittings, or when quick disconnect fittings are
removed.

Fuel filters are rated in microns. The word micron is the abbreviation for a micrometer, or one millionth of a meter. The
micron rating is the size of the smallest particles that will be captured by the filter media. As a reference, a human hair

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General Cleaning Instructions ISB, ISBe2, ISBe3, ISBe4, QSB4 [...]
Page i-16 Section i - Introduction

is 76 microns [0.003 in] in diameter. One micron measures 0.001 mm [0.00004 in.]. The contaminants being filtered
out are smaller than can be seen with the human eye, a magnifying glass, or a low powered microscope.

The tools used for fuel system troubleshooting and repair are to be cleaned regularly to avoid contamination. Like fuel
system parts, tools that are coated with oil or fuel attract airborne contaminants. Remember the following points
regarding your fuel system tools:

• Fuel system tools are to be kept as clean as possible.

• Clean and dry the tools before returning them to the tool box.

• If possible, store fuel system tools in sealed containers.

• Make sure fuel system tools are clean before use.

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ISB, ISBe2, ISBe3, ISBe4, QSB4 [...] Acronyms and Abbreviations
Section i - Introduction Page i-17

Acronyms and Abbreviations

General Information

The following list contains some of the acronyms and abbreviations used in this manual.

ANSI American National Standards Institute

API American Petroleum Institute
ASTM American Society of Testing and Materials
ATDC After Top Dead Center

BTU British Thermal Unit

BTDC Before Top Dead Center

°C Celsius

CAN Controller Area Network

CO Carbon Monoxide

CCA Cold Cranking Amperes

CARB California Air Resources Board

C.I.B. Customer Interface Box
C.I.D. Cubic Inch Displacement

CNG Compressed Natural Gas

CPL Control Parts List

cSt Centistokes

DEF Diesel Exhaust Fluid

DOC Diesel Oxidation Catalyst

DPF Diesel Particulate Filter

ECM Engine Control Module

EFC Electronic Fuel Control

EGR Exhaust Gas Recirculation

EPA Environmental Protection Agency

°F Fahrenheit

ft-lb Foot-Pound Force

FMI Failure Mode Indentifier

GVW Gross Vehicle Weight

Hg Mercury
hp Horsepower

H2O Water

inHg Inches of Mercury

in H20 Inches of Water

ICM Ignition Control Module

IEC International Electrotechnical Commission

km/l Kilometers per Liter

kPa Kilopascal

LNG Liquid Natural Gas

LPG Liquified Petroleum Gas
LTA Low Temperature Aftercooling

MCRS Modular Common Rail System

MIL Malfunction Indicator Lamp

MPa Megapascal
mph Miles Per Hour
mpq Miles Per Quart

N•m Newton-meter

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Acronyms and Abbreviations ISB, ISBe2, ISBe3, ISBe4, QSB4 [...]
Page i-18 Section i - Introduction

NOx Mono-Nitrogen Oxides

NG Natural Gas

O2 Oxygen
OBD On-Board Diagnostics
OEM Original Equipment Manufacturer

OSHA Occupational Safety and Health Administration

PID Parameter Identification Descriptions

ppm Parts Per Million

psi Pounds Per Square Inch

PTO Power Takeoff

REPTO Rear Power Take Off

RGT Rear Gear Train

rpm Revolutions Per Minute

SAE Society of Automotive Engineers
SCA Supplemental Coolant Additive
SCR Selective Catalytic Reduction

STC Step Timing Control

SID Subsystem Identification Descriptions

TDC Top Dead Center
VDC Volts of Direct Current

VGT Variable Geometry Turbocharger

VS Variable Speed

VSS Vehicle Speed Sensor

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ISB, ISBe2, ISBe3, ISBe4, QSB4 [...]
Section TF - Troubleshooting Fault Codes Page TF-a

Section TF - Troubleshooting Fault Codes

Section Contents

Page

Fault Code 1669 ........................................................................................................................................................TF-1

Catalyst Tank Level Sensor Circuit — Voltage Above Normal, or Shorted to High Source

Fault Code .................................................................................................................................................................TF-3

Fault Code 1671 ......................................................................................................................................................TF-12

Catalyst Tank Level — Data Valid but Below Normal Operational Range — Moderately Severe Level.

Fault Code ...............................................................................................................................................................TF-13

Fault Code 1673 ......................................................................................................................................................TF-15

Catalyst Tank Level - Data Erratic, Intermittent, or Incorrect.

Fault Code ...............................................................................................................................................................TF-17

Fault Code 1674 ......................................................................................................................................................TF-19

Exhaust Gas Temperature 2 Circuit — Voltage Below Normal, or Shorted to Low Source

Fault Code ...............................................................................................................................................................TF-21

Fault Code 1675 ......................................................................................................................................................TF-28

Exhaust Gas Temperature 2 Circuit — Voltage Above Normal, or Shorted to Low Source

Fault Code ...............................................................................................................................................................TF-30

Fault Code 1676 ......................................................................................................................................................TF-39

Exhaust Gas Temperature 2— Data Erratic, Intermittent, or Incorrect

Fault Code ...............................................................................................................................................................TF-41

Fault Code 1677 ......................................................................................................................................................TF-45

Catalyst Tank Temperature — Voltage Below Normal, or Shorted to Low Source

Fault Code ...............................................................................................................................................................TF-47

Fault Code 1678 ......................................................................................................................................................TF-54

Catalyst Tank Temperature — Voltage Above Normal, or Shorted to High Source

Fault Code ...............................................................................................................................................................TF-56

Fault Code 1679 ......................................................................................................................................................TF-65

Catalyst Tank Temperature — Data Erratic, Intermittent, or Incorrect

Fault Code ...............................................................................................................................................................TF-67

Fault Code 1681 ......................................................................................................................................................TF-73

Dosing Control Unit — Bad Intelligent Device or Component.

Fault Code ...............................................................................................................................................................TF-75

Fault Code 1682 ......................................................................................................................................................TF-77

Aftertreatment Diesel Exhaust Fluid Dosing Control Unit Input Lines - Condition Exists

Fault Code ...............................................................................................................................................................TF-80

Fault Code 1683 ......................................................................................................................................................TF-90

Catalyst Tank Heater Circuit — Voltage Above Normal, or Shorted to High Source

Fault Code ...............................................................................................................................................................TF-92

Fault Code 1684 ....................................................................................................................................................TF-102

Catalyst Tank Heater Circuit — Voltage Below Normal, or Shorted to Low Source

Fault Code .............................................................................................................................................................TF-104

Fault Code 1687 ....................................................................................................................................................TF-111

Catalyst Over Temperature - Data Valid but Above Normal Operational Range - Most Severe Level

Fault Code .............................................................................................................................................................TF-112

Fault Code 1689 ....................................................................................................................................................TF-116

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ISB, ISBe2, ISBe3, ISBe4, QSB4 [...]

Page TF-b Section TF - Troubleshooting Fault Codes

Real-Time Clock Power Interrupt - Data Erratic, Intermittent or Incorrect

Fault Code .............................................................................................................................................................TF-118

Fault Code 1692 ....................................................................................................................................................TF-127

Aftertreatment Outlet NOx Sensor - Voltage Below Normal, or Shorted to Low Source

Fault Code .............................................................................................................................................................TF-129

Fault Code 1694 ....................................................................................................................................................TF-137

Aftertreatment Outlet NOx Sensor - Data Erratic, Intermittent, or Incorrect

Fault Code .............................................................................................................................................................TF-139

Fault Code 1697 ....................................................................................................................................................TF-145

Aftertreatment #1 Air Enable Actuator — Voltage Above Normal, or Shorted to High Source.

Fault Code .............................................................................................................................................................TF-147

Fault Code 1698 ....................................................................................................................................................TF-153

Aftertreatment #1 Air Enable Actuator — Voltage Below Normal, or Shorted to Low Source.

Fault Code .............................................................................................................................................................TF-155

Fault Code 1699 ....................................................................................................................................................TF-165

Catalyst Tank Level Sensor — Data Erratic, Intermittent, or Incorrect.

Fault Code .............................................................................................................................................................TF-167

Fault Code 1711 ....................................................................................................................................................TF-173

Dosing Control Unit Data Link — Abnormal Update Rate

Fault Code .............................................................................................................................................................TF-175

Fault Code 1712 ....................................................................................................................................................TF-185

Catalyst Tank Heater Circuit — Data Valid But Below Normal Operating Range — Moderately Severe Level

Fault Code .............................................................................................................................................................TF-187

Fault Code 1713 ....................................................................................................................................................TF-193

Catalyst Tank Heater Circuit - Data Valid But Above Normal Operating Range - Moderately Severe Level

Fault Code .............................................................................................................................................................TF-195

Fault Code 1716 ....................................................................................................................................................TF-200

Auxiliary Temperature Sensor Input 1 Circuit - Root Cause Not Known

Fault Code .............................................................................................................................................................TF-202

Fault Code 1717 ....................................................................................................................................................TF-203

Exhaust Gas Temperature 1 — Data Valid but Above Normal Operational Range — Least Severe Level

Fault Code .............................................................................................................................................................TF-204

Fault Code 1718 ....................................................................................................................................................TF-207

Engine Misfire for Multiple Cylinders — Condition Exists.

Fault Code .............................................................................................................................................................TF-209

Fault Code 1845 ....................................................................................................................................................TF-212

Water-in-Fuel Indicator Sensor Circuit - Voltage Above Normal or Shorted to High Source (For Generator Engines

Only)

Fault Code .............................................................................................................................................................TF-214

Fault Code 1846 ....................................................................................................................................................TF-224

Water-in-Fuel Indicator Sensor Circuit - Voltage Below Normal or Shorted to Low Source (For Generator Engines

Only)

Fault Code .............................................................................................................................................................TF-226

Fault Code 1848 ....................................................................................................................................................TF-234

Intake Manifold 1 Temperature — Abnormal Rate of Change

Fault Code .............................................................................................................................................................TF-236

Fault Code 1849 ....................................................................................................................................................TF-243

Exhaust Gas Temperature 1 — Abnormal Rate of Change

Fault Code .............................................................................................................................................................TF-245

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ISB, ISBe2, ISBe3, ISBe4, QSB4 [...]
Section TF - Troubleshooting Fault Codes Page TF-c

Fault Code 1851 ....................................................................................................................................................TF-251

Exhaust Gas Temperature 2 — Abnormal Rate of Change

Fault Code .............................................................................................................................................................TF-253

Fault Code 1892 ....................................................................................................................................................TF-259

Wheel-Based Vehicle Speed — Data Valid but Below Normal Operational Range — Moderately Severe Level

Fault Code .............................................................................................................................................................TF-261

Fault Code 1911 ....................................................................................................................................................TF-269

Injector Metering Rail Number 1 Pressure - Data Valid But Above Normal Operating Range - Most Severe Level

Fault Code .............................................................................................................................................................TF-271

Fault Code 1992 ....................................................................................................................................................TF-283

Engine Crankshaft Speed/Position - Data Valid but Above Normal Operational Range - Moderately Severe Level

Fault Code .............................................................................................................................................................TF-285

Fault Code 2183 ....................................................................................................................................................TF-289

Engine Brake Actuator Driver 1 Circuit - Voltage Below Normal or Shorted to Low Source

Fault Code .............................................................................................................................................................TF-291

Fault Code 2185 ....................................................................................................................................................TF-302

Sensor Supply Voltage 4 Circuit - Voltage Above Normal or Shorted to High Source

Fault Code .............................................................................................................................................................TF-303

Fault Code 2186 ....................................................................................................................................................TF-308

Sensor Supply Voltage 4 Circuit - Voltage Below Normal or Shorted to Low Source

Fault Code .............................................................................................................................................................TF-309

Fault Code 2195 ....................................................................................................................................................TF-315

Auxiliary Equipment Sensor Input 3 Engine Protection Critical - Special Instructions

Fault Code .............................................................................................................................................................TF-316

Fault Code 2215b ..................................................................................................................................................TF-319

Fuel Pump Delivery Pressure - Data Valid But Below Normal Operational Range - Moderately Severe Level

Fault Code .............................................................................................................................................................TF-322

Fault Code 2215cl .................................................................................................................................................TF-340

Fuel Pump Delivery Pressure Low - Data Valid but Below Normal Operational Range - Moderately Severe Level

Fault Code .............................................................................................................................................................TF-342

Fault Code 2216b ..................................................................................................................................................TF-357

Fuel Pump Delivery Pressure - Data Valid but Above Normal Operational Range - Moderately Severe Level

Fault Code .............................................................................................................................................................TF-359

Fault Code 2216cl .................................................................................................................................................TF-365

Fuel Pump Delivery Pressure High - Data Valid but Above Normal Operational Range - Moderately Severe Level

Fault Code .............................................................................................................................................................TF-366

Fault Code 2217 ....................................................................................................................................................TF-371

Engine Control Module Calibration Program Memory (RAM) Corruption - Condition Exists

Fault Code .............................................................................................................................................................TF-373

Fault Code 2249 ....................................................................................................................................................TF-380

Injector Metering Rail 1 Pressure - Data Valid but Below Normal Operational Range - Most Severe Level

Fault Code .............................................................................................................................................................TF-381

Fault Code 2265 ....................................................................................................................................................TF-382

Electric Lift Pump for Engine Fuel Supply Circuit - Voltage Above Normal, or Shorted to High Source

Fault Code .............................................................................................................................................................TF-384

Fault Code 2266 ....................................................................................................................................................TF-400

Electric Lift Pump for Engine Fuel Supply Circuit - Voltage Below Normal, or Shorted to Low Source

Fault Code .............................................................................................................................................................TF-402

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ISB, ISBe2, ISBe3, ISBe4, QSB4 [...]

Page TF-d Section TF - Troubleshooting Fault Codes

Fault Code 2271 ....................................................................................................................................................TF-412

EGR Valve Position Sensor Circuit - Voltage Above Normal or Shorted to High Source

Fault Code .............................................................................................................................................................TF-413

Fault Code 2272 ....................................................................................................................................................TF-420

EGR Valve Position Sensor Circuit - Voltage Below Normal or Shorted to Low Source

Fault Code .............................................................................................................................................................TF-421

Fault Code 2273 ....................................................................................................................................................TF-430

EGR Valve Differential Pressure Sensor Circuit - Shorted High

Fault Code .............................................................................................................................................................TF-432

Fault Code 2274 ....................................................................................................................................................TF-439

EGR Valve Differential Pressure Sensor Circuit - Shorted Low

Fault Code .............................................................................................................................................................TF-441

Fault Code 2292 ....................................................................................................................................................TF-448

Fuel Inlet Meter Device - Data Valid but Above Normal Operational Range - Moderately Severe Level

Fault Code .............................................................................................................................................................TF-450

Fault Code 2293 ....................................................................................................................................................TF-456

Fuel Inlet Meter Device Flow Demand Lower Than Expected - Data Valid but Below Normal Operational Range -

Moderately Severe Level

Fault Code .............................................................................................................................................................TF-458

Fault Code 2311 ....................................................................................................................................................TF-462

Fueling Actuator Number 1 Circuit Error Conditions Exists

Fault Code .............................................................................................................................................................TF-464

Fault Code 2321 ....................................................................................................................................................TF-473

Engine Crankshaft Speed/Position - Data Erratic, Intermittent, or Incorrect

Fault Code .............................................................................................................................................................TF-475

Fault Code 2322 ....................................................................................................................................................TF-481

Backup Engine Speed/Position Sensor Number 2 - Data Erratic, Intermittent, or Incorrect

Fault Code .............................................................................................................................................................TF-483

Fault Code 2345b ..................................................................................................................................................TF-489

Turbocharger Speed - Invalid Rate of Change Detected

Fault Code .............................................................................................................................................................TF-490

Fault Code 2345cl .................................................................................................................................................TF-492

Turbocharger Speed Invalid Rate of Change Detected - Abnormal Rate of Change

Fault Code .............................................................................................................................................................TF-493

Fault Code 2346b ..................................................................................................................................................TF-496

Exhaust Gas Temperature - Data Above Normal

Fault Code .............................................................................................................................................................TF-497

Fault Code 2346cl .................................................................................................................................................TF-500

Turbocharger Turbine Inlet Temperature (Calculated) - Data Valid but Above Normal Operational Range - Least

Severe Level

Fault Code .............................................................................................................................................................TF-502

Fault Code 2347b ..................................................................................................................................................TF-509

Turbocharger Compressor Outlet Temperature - Data Above Normal

Fault Code .............................................................................................................................................................TF-511

Fault Code 2347cl .................................................................................................................................................TF-515

Turbocharger Compressor Outlet Air Temperature (Calculated) - Data Valid but Above Normal Range

Fault Code .............................................................................................................................................................TF-517

Fault Code 2348 ....................................................................................................................................................TF-527

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ISB, ISBe2, ISBe3, ISBe4, QSB4 [...]
Section TF - Troubleshooting Fault Codes Page TF-e

EGR Valve Failed Automatic Calibration Procedure

Fault Code .............................................................................................................................................................TF-528

Fault Code 2349 ....................................................................................................................................................TF-532

EGR Valve Control Circuit - Current Below Normal or Open Circuit

Fault Code .............................................................................................................................................................TF-534

Fault Code 2351 ....................................................................................................................................................TF-542

EGR Valve Control Circuit - Voltage Below Normal or Shorted to Low Source

Fault Code .............................................................................................................................................................TF-543

Fault Code 2352 ....................................................................................................................................................TF-550

EGR Valve Control Circuit - Voltage Above Normal or Shorted to High Source

Fault Code .............................................................................................................................................................TF-552

Fault Code 2353 ....................................................................................................................................................TF-557

EGR Valve Control Circuit - Current Above Normal or Grounded Circuit

Fault Code .............................................................................................................................................................TF-558

Fault Code 2357 ....................................................................................................................................................TF-564

EGR Valve Control - Mechanical System Not Responding Properly or Out of Adjustment

Fault Code .............................................................................................................................................................TF-566

Fault Code 2359 ....................................................................................................................................................TF-572

EGR Differential Pressure Sensor - Data Valid But Above Normal Operating Range - Moderately Severe Level

Fault Code .............................................................................................................................................................TF-574

Fault Code 2362 ....................................................................................................................................................TF-582

Engine Brake Actuator Circuit #1 - Voltage Below Normal or Shorted to Low Source

Fault Code .............................................................................................................................................................TF-583

Fault Code 2363 ....................................................................................................................................................TF-594

Engine Brake Actuator Circuit #2 - Voltage Below Normal or Shorted to Low Source

Fault Code .............................................................................................................................................................TF-595

Fault Code 2366 ....................................................................................................................................................TF-605

Engine Brake Actuator Circuit #1 - Voltage Above Normal or Shorted to High Source

Fault Code .............................................................................................................................................................TF-607

Fault Code 2367 ....................................................................................................................................................TF-617

Engine Brake Actuator Circuit #2 - Voltage Above Normal or Shorted to High Source

Fault Code .............................................................................................................................................................TF-618

Fault Code 2373 ....................................................................................................................................................TF-627

Exhaust Gas Pressure Sensor Circuit - Shorted High

Fault Code .............................................................................................................................................................TF-628

Fault Code 2374 ....................................................................................................................................................TF-635

Exhaust Gas Pressure Sensor Circuit - Shorted Low

Fault Code .............................................................................................................................................................TF-636

Fault Code 2375 ....................................................................................................................................................TF-644

Exhaust Gas Recirculation (EGR) Temperature Sensor Circuit - Voltage Above Normal or Shorted to High Source

Fault Code .............................................................................................................................................................TF-646

Fault Code 2376 ....................................................................................................................................................TF-656

Recirculation Exhaust Gas Temperature Sensor Circuit - Voltage Below Normal or Shorted to Low Source

Fault Code .............................................................................................................................................................TF-658

Fault Code 2377 ....................................................................................................................................................TF-666

Fan Control Circuit - Voltage Above Normal or Shorted to High Source

Fault Code .............................................................................................................................................................TF-668

Fault Code 2381 ....................................................................................................................................................TF-677

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ISB, ISBe2, ISBe3, ISBe4, QSB4 [...]

Page TF-f Section TF - Troubleshooting Fault Codes

Turbocharger Position Sensor Circuit - Shorted High

Fault Code .............................................................................................................................................................TF-678

Fault Code 2382 ....................................................................................................................................................TF-685

Turbocharger Position Sensor Circuit - Shorted Low

Fault Code .............................................................................................................................................................TF-686

Fault Code 2383 ....................................................................................................................................................TF-693

Variable Geometry Turbocharger Actuator Circuit - Current Below Normal, or Open Circuit

Fault Code .............................................................................................................................................................TF-695

Fault Code 2384b ..................................................................................................................................................TF-704

VGT Actuator Driver Circuit - Voltage Below Normal, or Shorted to Low Source

Fault Code .............................................................................................................................................................TF-705

Fault Code 2384cl .................................................................................................................................................TF-713

VGT Actuator - Voltage Below Normal or Shorted to Low Source

Fault Code .............................................................................................................................................................TF-715

Fault Code 2385b ..................................................................................................................................................TF-722

VGT Actuator Driver Circuit - Voltage Above Normal or Shorted to High Source

Fault Code .............................................................................................................................................................TF-723

Fault Code 2385cl .................................................................................................................................................TF-728

VGT Actuator - Voltage Above Normal or Shorted to High Source

Fault Code .............................................................................................................................................................TF-730

Fault Code 2386 ....................................................................................................................................................TF-740

Turbocharger Actuator Motor Circuit - Current Above Normal

Fault Code .............................................................................................................................................................TF-741

Fault Code 2387 ....................................................................................................................................................TF-749

Turbocharger Actuator Motor - Mechanical System Not Responding Properly

Fault Code .............................................................................................................................................................TF-750

Fault Code 2388 ....................................................................................................................................................TF-755

Variable Geometry Turbocharger Actuator Position Failed Automatic Calibration Procedure - Out of Calibration

Fault Code .............................................................................................................................................................TF-756

Fault Code 2448 ....................................................................................................................................................TF-761

Coolant Level - Data Valid But Below Normal Operational Range - Least Severe Level

Fault Code .............................................................................................................................................................TF-763

Fault Code 2554 ....................................................................................................................................................TF-764

Exhaust Pressure Sensor Circuit - Data Erratic, Intermittent, or Incorrect

Fault Code .............................................................................................................................................................TF-765

Fault Code 2555 ....................................................................................................................................................TF-767

Intake Air Heater #1 Circuit - Voltage Above Normal or Shorted to High Source

Fault Code .............................................................................................................................................................TF-768

Fault Code 2556 ....................................................................................................................................................TF-778

Intake Air Heater #1 Circuit - Voltage Below Normal or Shorted to Low Source

Fault Code .............................................................................................................................................................TF-779

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ISB, ISBe2, ISBe3, ISBe4, QSB4 [...] Catalyst Tank Level Sensor Circuit — Voltage Above Norm [...]
Section TF - Troubleshooting Fault Codes Page TF-1

Fault Code 1669

Catalyst Tank Level Sensor Circuit — Voltage Above Normal, or Shorted to High Source

CODES REASON EFFECT

Fault Code: 1669
PID(P), SID(S):
SPN: 1761
FMI: 3
Lamp: Amber
SRT:

Catalyst Tank Level Sensor
Circuit — Voltage Above Normal,
or Shorted to High Source. High
signal voltage detected at the
catalyst tank level sensor circuit.

Catalyst solution injection into the
aftertreatment system is disabled.

Circuit: Catalyst Tank Level Sensor.

Circuit Description:

The catalyst tank level sensor is used to monitor the catalyst solution level inside the catalyst tank. The catalyst tanks
level sensor is a combination sensor with the catalyst solution temperature sensor. The level and temperature sensors
share a common return circuit.

Component Location:

The catalyst tank level sensor is located in the catalyst tank. Location of the tank and level sensor is OEM dependent.

Shop Talk:

The catalyst tank level sensor shares supply and return wires in the engine harness with other sensors. Opens and
shorts in the engine harness can cause multiple fault codes to be active.

Before troubleshooting Fault Code 1669, check for multiple faults.

Possible causes of this fault code include:

• Open return circuit in the harness, connectors, or sensor

• Signal circuit shorted to sensor supply or battery voltage.

On-Board Diagnostics (OBD) Information (Euro 4 Certified Engines):

• The ECM illuminates the malfunction indicator lamp (MIL) when the diagnostic runs and fails.

• The ECM turns OFF the malfunction indicator lamp (MIL) after 3 consecutive ignition cycles that the diagnostic runs
and does not fail. The MIL lamp and fault code can also be cleared using the INSITE™ service tool.

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Catalyst Tank Level Sensor Circuit — Voltage Above Norm [...] ISB, ISBe2, ISBe3, ISBe4, QSB4 [...]
Page TF-2 Section TF - Troubleshooting Fault Codes

• The fault code will be cleared from memory after 40 consecutive drive cycles where the diagnostic runs and passes.

On-Board Diagnostics (OBD) Information (Euro 4 Stage 1+ Certified Engines):

• The ECM illuminates the malfunction indicator lamp (MIL) when the diagnostic runs and fails.

• An engine torque derate will be activated after 50 hours of engine operation with the fault code active.

• The ECM turns OFF the malfunction indicator lamp (MIL) after 1 ignition cycle that the diagnostic runs and does not
fail. The MIL lamp cannot be cleared using the INSITE™ service tool.

• The fault code will be cleared from memory after 400 days or 9600 hours of engine operation.

Refer to Troubleshooting Fault Code t05-1669

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ISB, ISBe2, ISBe3, ISBe4, QSB4 [...]
Section TF - Troubleshooting Fault Codes Page TF-3

FAULT CODE 1669 - Catalyst Tank Level Sensor Circuit — Voltage Above

Normal, or Shorted to High Source

TROUBLESHOOTING SUMMARY

CAUTION
To reduce the possibility of damaging a new ECM, all other active fault codes must be investigated prior to
replacing the ECM.

CAUTION
To reduce the possibility of pin and harness damage, use the following test leads when taking a
measurement: Part Number 3822758 - male Deutsch™/AMP™/Metri-Pack™ test lead and Part Number 3822917

- female Deutsch™/AMP™/Metri-Pack™ test lead.

STEPS

SPECIFICATIONS SRT CODE

STEP 1: Check the fault codes.

STEP 1A: Check for sensor supply fault

codes.

STEP 1B: Check for an inactive fault code. Fault Code 1669 inactive?

Fault Code 227 active?

STEP 2: Check the catalyst tank level sensor and circuit.

STEP 2A: Inspect the catalyst tank level

sensor and connector pins.

STEP 2B: Check the circuit response. Fault Code 1668 active and fault

STEP 2C: Check the sensor supply

voltage and return circuit.

STEP 2D: Check the fault codes and verify

sensor condition.

Dirty or damaged pins?

code 1669 inactive?

4.75 to 5.25 VDC?

Fault Code 1669 active?

STEP 3: Check the ECM and engine harness.

STEP 3A: Inspect the ECM and engine

harness connector pins.

STEP 3A-1: Check the engine control

module response.

STEP 3A-2: Check for an active fault

code.

STEP 3B: Inspect engine control module

and engine harness connector
pins.

STEP 3B-1: Check the sensor supply

voltage and return circuit.

STEP 3B-2: Check for an active fault

code.

Dirty or damaged pins?

Fault Code 1668 active and fault
code 1669 inactive?

Fault code 1669 inactive?

Dirty or damaged pins?

4.75 to 5.25 VDC?

Fault Code 1669 inactive?

STEP 4: Clear the fault codes.

STEP 4A: Disable the fault code. Fault Code 1669 inactive?

STEP 4B: Clear the inactive fault codes. All fault codes cleared?

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ISB, ISBe2, ISBe3, ISBe4, QSB4 [...]

Page TF-4 Section TF - Troubleshooting Fault Codes

TROUBLESHOOTING STEP

STEP 1: Check the fault codes

STEP 1A: Check for sensor supply fault codes.

Condition:

• Turn keyswitch ON

• Connect INSITE™ electronic service tool.

Action Specification/Repair Next Step

Check for sensor supply fault codes.

• Use INSITE™ electronic service tool to read
the fault codes.

STEP 1B: Check for an inactive fault code.

Condition:

• Turn keyswitch ON

• Connect INSITE™ electronic service tool.

Action Specification/Repair Next Step

Check for inactive fault code.

• Use INSITE™ electronic service tool to read
the fault codes.

Fault Code 227 active?

YES

Fault Code 227 active?

NO

Fault Code 1669 is inactive?

YES

Refer to
Fault Code
227

1B

Use the
following
procedure for
an inactive or
intermittent
fault code.
Refer to
Procedure
019-362 in
Section 19.

Fault Code 1669 is inactive?

NO

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2A

ISB, ISBe2, ISBe3, ISBe4, QSB4 [...]
Section TF - Troubleshooting Fault Codes Page TF-5

STEP 2: Check the catalyst tank level sensor and circuit.

STEP 2A: Inspect the catalyst tank level sensor and connector pins.

Condition:

• Turn keyswitch OFF.

• Disconnect the catalyst tank level sensor from the engine harness.

Action Specification/Repair Next Step

Inspect the engine harness and catalyst tank
level sensor connector pins for the following:

• Loose connector

• Corroded pins

• Bent or broken pins

• Pushed back or expanded pins

Dirty or damaged pins?

YES

Repair:

A defective connection has been detected in
the sensor or harness connector.

• Moisture in or on the connector

• Missing or damaged connector seals

• Dirt or debris in or on the connector pins

• Connector shell broken

• Wire insulation damage

Clean the connector and pins.

Repair the damaged harness, connector, or
pins if possible. Refer to Procedure 019-043
in Section 19.

• Damaged connector locking tab.

Use the following procedure for general
inspection techniques. Refer to Procedure
019-361 in Section 19.

Dirty or damaged pins?

NO

STEP 2B: Check the circuit response.

Condition:

• Turn keyswitch OFF.

• Disconnect the catalyst tank level sensor from the engine harness.

• Turn keyswitch ON.

• Connect INSITE™ electronic service tool.

Action Specification/Repair Next Step

4A

2B

Check the appropriate circuit response after 30
seconds.

• Using INSITE™ electronic service tool read
the fault codes.

Fault Code 1668 active and fault code 1669
inactive?

YES

Fault Code 1668 active and fault code 1669
inactive?

NO

2C

3A

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ISB, ISBe2, ISBe3, ISBe4, QSB4 [...]

Page TF-6 Section TF - Troubleshooting Fault Codes

STEP 2C: Check the sensor supply voltage and return circuit.

Condition:

• Turn keyswitch OFF.

• Disconnect the catalyst tank level sensor from the engine harness.

• Turn keyswitch ON.

Action Specification/Repair Next Step

Check the supply voltage and return circuit.

• Measure the voltage from the CATALYST
TANK LEVEL +5 VDC SUPPLY pin to the
CATALYST TANK LEVEL RETURN pin at the
sensor connector of the engine harness.

Refer to the wiring diagram for connector pin
identification.

4.75 to 5.25 VDC?

YES

4.75 to 5.25 VDC?

NO

2D

3B

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ISB, ISBe2, ISBe3, ISBe4, QSB4 [...]
Section TF - Troubleshooting Fault Codes Page TF-7

STEP 2D: Check the fault codes and verify sensor condition

Condition:

• Turn keyswitch OFF.

• Connect the catalyst tank level sensor to the engine harness.

• Turn keyswitch ON.

• Connect INSITE™ electronic service tool.

Action Specification/Repair Next Step

Check for the approriate circuit response after 30
seconds.

• Use INSITE™ electronic service tool to read
the fault codes.

Fault code 1669 is active?

YES

Repair:

A damaged sensor has been detected.

Replace the catalyst tank level sensor. Refer
to OEM service manual.

Fault code 1669 is active?

NO

Repair:

None. The removal and reinstallation of the
connector corrected the problem.

STEP 3: Check the ECM and engine harness.

STEP 3A: Inspect the ECM and engine harness connector pins.

Condition:

• Turn keyswitch OFF.

• Disconnect the engine harness from the ECM connector.

Action Specification/Repair Next Step

4A

4A

Inspect the engine harness and ECM engine
connector pins for the following:

• Loose connector

• Corroded pins

• Bent or broken pins

• Pushed back or expanded pins

• Moisture in or on the connector

• Missing or damaged connector seals

• Dirt or debris in or on the connector pins

• Connector shell broken

• Wire insulation damage

• Damaged connector locking tab.

Use the following procedure for general
inspection techniques. Refer to Procedure
019-361 in Section 19.

Dirty or damaged pins?

YES

Repair:

A damaged connection has been detected in
the ECM engine connector or the engine
harness connector.

Clean the connector and pins.

Repair the damaged harness, connector, or
pins if possible. Refer to Procedure 019-043
in Section 19.

Dirty or damaged pins?

NO

4A

3A-1

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ISB, ISBe2, ISBe3, ISBe4, QSB4 [...]

Page TF-8 Section TF - Troubleshooting Fault Codes

STEP 3A-1: Check the engine control module response.

Condition:

• Turn keyswitch OFF

• Disconnect the engine harness from the ECM

• Turn keyswitch ON

• Connect INSITE™ electronic service tool.

Action Specification/Repair Next Step

Check the appropriate circuit response after 30
seconds.

• Use INSITE™ electronic service tool to read
the fault codes.

STEP 3A-2: Check for an active fault code.

Condition:

• Connect all components.

• Turn keyswitch ON

• Connect INSITE™ electronic service tool.

Action Specification/Repair Next Step

Check the appropriate circuit response after 30
seconds.

• Use INSITE™ electronic service tool to read
the fault codes.

Fault Code 1668 active and fault code 1669
inactive?

YES

Fault Code 1668 active and fault code 1669
inactive?

NO

Repair:

Replace the ECM. Refer to Procedure
019-031 in Section 19.

Fault code 1669 inactive?

YES

Repair:

None. The removal and reinstallation of the
connector corrected the problem.

3A-2

4A

4A

Fault code 1669 active?

4A

NO

Repair:

A pin-to-pin short circuit has been detected
on the signal line of the engine harness.

Repair or replace the engine harness. Refer
to Procedure 019-043 in Section 19.

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ISB, ISBe2, ISBe3, ISBe4, QSB4 [...]
Section TF - Troubleshooting Fault Codes Page TF-9

STEP 3B: Inspect engine control module and engine harness connector pins.

Condition:

• Turn keyswitch OFF.

• Disconnect the engine harness from the ECM.

Action Specification/Repair Next Step

Inspect the engine harness and engine control
module engine connector pins for the following:

• Loose connector

• Corroded pins

• Bent or broken pins

• Pushed back or expanded pins

• Moisture in or on the connector

• Missing or damaged connector seals

• Dirt or debris in or on the connector pins

• Connector shell broken

• Wire insulation damage

• Damaged connector locking tab.

Use the following procedure for general
inspection techniques. Refer to Procedure
019-361 in Section 19.

Dirty or damaged pins?

YES

Repair:

A damaged connection has been detected in
the engine control module engine connector
or engine harness connector.

Clean the connector and pins.

Repair the damaged harness, connector or
pins if possible. Refer to Procedure 019-043
in Section 19.

Dirty or damaged pins?

NO

4A

3B-1

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ISB, ISBe2, ISBe3, ISBe4, QSB4 [...]

Page TF-10 Section TF - Troubleshooting Fault Codes

STEP 3B-1: Check the sensor supply voltage and return circuit.

Condition:

• Turn keyswitch OFF.

• Disconnect the engine harness from the ECM engine connector.

• Turn keyswitch ON.

Action Specification/Repair Next Step

Check the supply voltage and return circuit.

• Measure the voltage from the CATALYST
TANK LEVEL +5 VDC SUPPLY pin and the
CATALYST TANK LEVEL RETURN pin at the
engine control module engine connector.

Refer to the wiring diagram for connector pin
identification.

4.75 to 5.25 VDC?

YES

4.75 to 5.25 VDC?

NO

Repair:

Replace the ECM. Refer to Procedure
019-031 in Section 19.

3B-2

4A

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ISB, ISBe2, ISBe3, ISBe4, QSB4 [...]
Section TF - Troubleshooting Fault Codes Page TF-11

STEP 3B-2: Check for an active fault code.

Condition:

• Connect all components.

• Turn keyswitch ON

• Connect INSITE™ electronic service tool.

Action Specification/Repair Next Step

Check for the appropriate circuit response after
30 seconds.

• Use INSITE™ electronic service tool to read
the fault codes.

STEP 4: Clear the fault code.

STEP 4A: Disable the fault code.

Condition:

• Connect all components.

• Turn keyswitch ON.

• Connect INSITE™ electronic service tool.

Fault Code 1669 inactive?

YES

Repair:

None. The removal and reinstallation of the
connector corrected the problem.

Fault Code 1669 inactive?

NO

Repair:

An open RETURN circuit has been detected
in the engine harness.

Repair or replace the engine harness. Refer
to Procedure 019-043 in Section 19.

4A

4A

Action Specification/Repair Next Step

Disable the fault code.

• Start the engine and let it idle for 1 minute.

• Use INSITE™ electronic service tool to verify
the fault code is inactive.

STEP 4B: Clear the inactive fault codes.

Condition:

• Connect all components.

• Turn keyswitch ON.

• Connect INSITE™ electronic service tool.

Action Specification/Repair Next Step

Clear the inactive fault codes.

• Use INSITE™ electronic service tool to erase
the inactive fault codes.

Fault Code 1669 inactive?

YES

Fault Code 1669 inactive?

NO

All fault codes cleared?

YES

All fault codes cleared?

NO

4B

1A

Repair
complete

Appropriate
troubleshooti
ng steps

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Catalyst Tank Level — Data Valid but Below Normal Opera [...] ISB, ISBe2, ISBe3, ISBe4, QSB4 [...]
Page TF-12 Section TF - Troubleshooting Fault Codes

Fault Code 1671

Catalyst Tank Level — Data Valid but Below Normal Operational Range — Moderately

Severe Level.

CODES REASON EFFECT

Fault Code: 1671
PID(P), SID(S):
SPN: 1761
FMI: 1/18
Lamp: Maintenance
SRT:

Catalyst Tank Level — Data Valid
but Below Normal Operational
Range — Moderately Severe
Level. Low catalyst solution level
has been detected in the catalyst
solution tank.

None on performance.

Circuit: Aftertreatment Control System

Circuit Description:

The catalyst solution level sensor is used to monitor the catalyst solution level inside the catalyst tank.

Component Location:

The catalyst solution level sensor is located in the catalyst solution tank. Location of the tank and level sensor is OEM
dependent.

Shop Talk:

Fault code 1671 is triggered when low catalyst solution level has been detected in the catalyst solution tank. Add
catalyst solution to the tank. This fault code is only a warning for low catalyst tank solution level.

On-Board Diagnostic (OBD) Information:

• The ECM illuminates the appropriate amber or red fault lamp when the diagnostic runs and fails.

• The ECM turns off the appropriate fault lamp when the diagnostic runs and passes.

Refer to Troubleshooting Fault Code t05-1671

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ISB, ISBe2, ISBe3, ISBe4, QSB4 [...]
Section TF - Troubleshooting Fault Codes Page TF-13

FAULT CODE 1671 - Catalyst Tank Level - Data Valid But Below Normal

Operational Range - Moderately Severe Level

TROUBLESHOOTING SUMMARY

CAUTION
To reduce the possibility of damaging a new ECM, all other active fault codes must be investigated prior to
replacing the ECM.

CAUTION
To reduce the possibility of pin and harness damage, use the following test leads when taking a
measurement: Part Number 3822758 - male Deutsch™/AMP™/Metri-Pack™ test lead and Part Number 3822917

- female Deutsch™/AMP™/Metri-Pack™ test lead.

STEPS

SPECIFICATIONS SRT CODE

STEP 1: Check the fault codes.

STEP 1A: Read the fault codes. Fault Code 1671 active?

STEP 2: Clear the fault code.

STEP 2A: Disable the fault code. Fault Code 1671 inactive?

STEP 2B: Clear the inactive fault code. All faults cleared?

TROUBLESHOOTING STEP

STEP 1: Check the fault codes.

STEP 1A: Read the fault codes.

Condition:

• Turn keyswitch ON.

• Connect INSITE™ electronic service tool.

Action Specification/Repair Next Step

Read fault codes.

• Use INSITE™ electronic service tool to read
the fault codes.

Fault code 1671 active?

YES

Repair:

Low catalyst solution level has been
detected.

Add catalyst solution to the catalyst solution
tank.

2A

Fault code 1671 active?

NO

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2A

ISB, ISBe2, ISBe3, ISBe4, QSB4 [...]

Page TF-14 Section TF - Troubleshooting Fault Codes

STEP 2: Clear the fault code.

STEP 2A: Disable the fault code.

Condition:

• Connect all components

• Turn the keyswitch ON

• Connect INSITE™ electronic service tool.

Action Specification/Repair Next Step

Disable the fault code.

• Use INSITE™ electronic service tool to verify
that the fault code is inactive.

STEP 2B: Clear the inactive fault codes.

Condition:

• Connect all components

• Turn the keyswitch ON

• Connect INSITE™ electronic service tool.

Action Specification/Repair Next Step

Clear the inactive fault codes.

• Use INSITE™ electronic service tool to clear
all the inactive fault codes.

Fault Code 1671 inactive?

YES

Fault Code 1671 inactive?

NO

All faults cleared?

YES

All faults cleared?

NO

2B

1A

Repair
complete.

Appropriate
troubleshooti
ng steps.

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ISB, ISBe2, ISBe3, ISBe4, QSB4 [...] Catalyst Tank Level - Data Erratic, Intermittent, or In [...]
Section TF - Troubleshooting Fault Codes Page TF-15

Fault Code 1673

Catalyst Tank Level - Data Erratic, Intermittent, or Incorrect.

CODES REASON EFFECT

Fault Code: 1673
PID(P), SID(S):
SPN: 1761
FMI: 1
Lamp: Amber
SRT:

Catalyst Tank Level — Data Valid
but Below Normal Operational
Range — Most Severe Level. No
catalyst solution has been
detected in the catalyst solution
tank.

Catalyst solution injection into the
aftertreatment system is disabled.

Circuit: Aftertreatment Control System

Circuit Description:

The catalyst solution level sensor is used to monitor the catalyst solution level inside the catalyst tank.

Component Location:

The catalyst solution level sensor is located in the catalyst solution tank. Location of the tank and level sensor is OEM
dependent.

Shop Talk:

Fault code 1673 is triggered when the catalyst solution level sensor has detected that the catalyst tank is empty.
Catalyst solution may still be visible inside the tank when this fault code is active. Add catalyst solution to the tank.

On-Board Diagnostics (OBD) Information (Euro 4 Certified Engines):

• The ECM illuminates the malfunction indicator lamp (MIL) when the diagnostic runs and fails.

• The ECM turns OFF the malfunction indicator lamp (MIL) after 3 consecutive ignition cycles that the diagnostic runs
and does not fail. The MIL lamp and fault code can also be cleared using the INSITE™ service tool.

• The fault code will be cleared from memory after 40 consecutive drive cycles where the diagnostic runs and passes.

On-Board Diagnostics (OBD) Information (Euro 4 Stage 1+ Certified Engines):

• The ECM illuminates the malfunction indicator lamp (MIL) when the diagnostic runs and fails.

• An engine torque derate will be activated after 50 hours of engine operation with the fault code active.

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Catalyst Tank Level - Data Erratic, Intermittent, or In [...] ISB, ISBe2, ISBe3, ISBe4, QSB4 [...]
Page TF-16 Section TF - Troubleshooting Fault Codes

• The ECM turns OFF the malfunction indicator lamp (MIL) after 1 ignition cycle that the diagnostic runs and does not
fail. The MIL lamp cannot be cleared using the INSITE™ service tool.

• The fault code will be cleared from memory after 400 days or 9600 hours of engine operation.

Refer to Troubleshooting Fault Code t05-1673

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ISB, ISBe2, ISBe3, ISBe4, QSB4 [...]
Section TF - Troubleshooting Fault Codes Page TF-17

FAULT CODE 1673 - Catalyst Tank Level - Data Erratic, Intermittent, or

Incorrect

TROUBLESHOOTING SUMMARY

CAUTION
To reduce the possibility of damaging a new ECM, all other active fault codes must be investigated prior to
replacing the ECM.

CAUTION
To reduce the possibility of pin and harness damage, use the following test leads when taking a
measurement: Part Number 3822758 - male Deutsch™/AMP™/Metri-Pack™ test lead and Part Number 3822917

- female Deutsch™/AMP™/Metri-Pack™ test lead.

STEPS

SPECIFICATIONS SRT CODE

STEP 1: Check the fault codes.

STEP 1A: Read the fault codes. Fault code 1673 active?

STEP 2: Clear the fault code.

STEP 2A: Disable the fault code. Fault code 1673 inactive?

STEP 2B: Clear the inactive fault code. All faults cleared?

TROUBLESHOOTING STEP

STEP 1: Check the fault codes.

STEP 1A: Read the fault codes.

Condition:

• Turn keyswitch ON.

• Connect INSITE™ electronic service tool.

Action Specification/Repair Next Step

Read fault codes.

• Using INSITE™ electronic service tool read
the fault codes.

Fault code 1673 active?

YES

Repair:

No catalyst solution has been detected in the
catalyst solution tank.

Add catalyst solution to the catalyst solution
tank.

2A

Fault code 1673 active?

NO

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2A

ISB, ISBe2, ISBe3, ISBe4, QSB4 [...]

Page TF-18 Section TF - Troubleshooting Fault Codes

STEP 2: Clear the fault code.

STEP 2A: Disable the fault code.

Condition:

• Connect all components

• Turn the keyswitch ON

• Connect INSITE™ electronic service tool.

Action Specification/Repair Next Step

Disable the fault code.

• Use INSITE™ electronic service tool to verify
that the fault code is inactive.

STEP 2B: Clear the inactive fault codes.

Condition:

• Connect all components

• Turn the keyswitch ON

• Connect INSITE™ electronic service tool.

Action Specification/Repair Next Step

Clear the inactive fault codes.

• Use INSITE™ electronic service tool to erase
all the inactive fault codes.

Fault code 1673 inactive?

YES

Fault code 1673 inactive?

NO

All faults cleared?

YES

All faults cleared?

NO

2B

1A

Repair
complete.

Appropriate
troubleshooti
ng steps.

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ISB, ISBe2, ISBe3, ISBe4, QSB4 [...] Exhaust Gas Temperature 2 Circuit — Voltage Below Norma [...]
Section TF - Troubleshooting Fault Codes Page TF-19

Fault Code 1674

Exhaust Gas Temperature 2 Circuit — Voltage Below Normal, or Shorted to Low Source

CODES REASON EFFECT

Fault Code: 1674
PID(P), SID(S):
SPN: 3249
FMI: 4
Lamp: Amber
SRT:

Exhaust Gas Temperature 2
Circuit — Voltage Below Normal,
or Shorted to Low Source. Low
signal voltage detected at the
catalyst exhaust temperature
sensor circuit.

Default temperature used for catalyst exhaust
temperature.

Circuit: Exhaust Gas Temperature 2

Circuit Description:

The catalyst outlet temperature sensor is used by the electronic control module (ECM) to monitor the engine exhaust
temperature exiting the catalyst unit. The ECM monitors the voltage on the signal pin and converts this to a
temperature value.

Component Location:

The catalyst outlet temperature sensor is located in the aftertreatment system. It is located in the outlet of the
aftertreatment catalyst unit.

Shop Talk:

The catalyst outlet temperature sensor shares return wires in the engine harness with other sensors. A shorted return
can cause multiple fault codes to be active.

Possible causes of this fault code include:

• Signal shorted to ground in the harness

• Signal shorted to return or ground in the sensor.

On-Board Diagnostics (OBD) Information (Euro 4 Certified Engines):

• The ECM illuminates the malfunction indicator lamp (MIL) when the diagnostic runs and fails.

• The ECM turns OFF the malfunction indicator lamp (MIL) after 3 consecutive ignition cycles that the diagnostic runs
and does not fail. The MIL lamp and fault code can also be cleared using the INSITE™ service tool.

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Exhaust Gas Temperature 2 Circuit — Voltage Below Norma [...] ISB, ISBe2, ISBe3, ISBe4, QSB4 [...]
Page TF-20 Section TF - Troubleshooting Fault Codes

• The fault code will be cleared from memory after 40 consecutive drive cycles where the diagnostic runs and passes.

On-Board Diagnostics (OBD) Information (Euro 4 Stage 1+ Certified Engines):

• The ECM illuminates the malfunction indicator lamp (MIL) when the diagnostic runs and fails.

• An engine torque derate will be activated after 50 hours of engine operation with the fault code active.

• The ECM turns OFF the malfunction indicator lamp (MIL) after 1 ignition cycle that the diagnostic runs and does not
fail. The MIL lamp cannot be cleared using the INSITE™ service tool.

• The fault code will be cleared from memory after 400 days or 9600 hours of engine operation.

Refer to Troubleshooting Fault Code t05-1674

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Section TF - Troubleshooting Fault Codes Page TF-21

FAULT CODE 1674 - Exhaust Gas Temperature 2 Circuit - Voltage Below

Normal, or Shorted to Low Source

TROUBLESHOOTING SUMMARY

CAUTION
To reduce the possibility of damaging a new ECM, all other active fault codes must be investigated prior to
replacing the ECM.

CAUTION
To reduce the possibility of pin and harness damage, use the following test leads when taking a
measurement: Part Number 3822758 - male Deutsch™/AMP™/Metri-Pack™ test lead and Part Number 3822917

- female Deutsch™/AMP™/Metri-Pack™ test lead.

STEPS

SPECIFICATIONS SRT CODE

STEP 1: Check the fault codes.

STEP 1A: Check for an inactive fault code. Fault Code 1674 inactive?

STEP 2: Check the exhaust gas temperature #2 sensor and circuit.

STEP 2A: Inspect the exhaust gas

temperature #2 sensor and
connector pins.

STEP 2B: Check the circuit response. Fault Code 1675 active and fault

STEP 2C: Check the fault codes and verify

sensor condition.

Dirty or damaged pins?

Code 1674 inactive?

Fault Code 1674 is active?

STEP 3: Check the ECM and engine harness.

STEP 3A: Inspect the ECM and engine

harness connector pins.

STEP 3B: Check the circuit response. Fault Code 1675 active and Fault

STEP 3C: Check for a pin-to-pin short

circuit in the engine harness.

STEP 3D: Check for a pin short circuit to

ground.

STEP 3E: Check for an inactive fault code. Fault Code 1674 inactive?

Dirty or damaged pins?

Code 1674 inactive?

Greater than 100K ohms?

Greater than 100K ohms?

STEP 4: Clear the fault codes.

STEP 4A: Disable the fault code. Fault Code 1674 inactive?

STEP 4B: Clear the inactive fault codes. All fault codes cleared?

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Page TF-22 Section TF - Troubleshooting Fault Codes

TROUBLESHOOTING STEP

STEP 1: Check the fault codes.

STEP 1A: Check for an inactive fault code.

Condition:

• Turn keyswitch ON.

• Connect INSITE™ electronic service tool.

Action Specification/Repair Next Step

Check for an inactive fault code.

• Use INSITE™ to read the fault codes.

Fault Code 1674 inactive?

YES

Fault Code 1674 inactive?

NO

STEP 2: Check the exhaust gas temperature #2 sensor and circuit.

STEP 2A: Inspect the exhaust gas temperature #2 sensor and connector pins.

Condition:

• Turn keyswitch OFF.

• Disconnect the exhaust gas temperature #2 sensor from the engine harness.

Action Specification/Repair Next Step

Inspect the engine harness and exhaust gas
temperature #2 sensor connector pins for the
following:

• Loose connector

• Corroded pins

• Bent or broken pins

• Pushed back or expanded pins

• Moisture in or on the connector

• Missing or damaged connector seals

• Dirt or debris in or on the connector pins

• Connector shell broken

• Wire insulation damage

• Damaged connector locking tab.

Use the following procedure for general
inspection techniques. Refer to Procedure
019-361 in Section 19.

Dirty or damaged pins?

YES

Repair:

A damaged connection has been detected in
the sensor or harness connector.

Clean the connector and pins.

Repair the damaged harness, connector, or
pins if possible. Refer to Procedure 019-071
in Section 19.

Dirty or damaged pins?

NO

Use the
following
procedure for
an inactive or
intermittent
fault code.
Refer to
Procedure
019-362 in
Section 19.

2A

4A

2B

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Section TF - Troubleshooting Fault Codes Page TF-23

STEP 2B: Check the circuit response.

Condition:

• Turn keyswitch OFF.

• Disconnect the exhaust gas temperature #2 sensor from the engine harness.

• Turn keyswitch ON.

• Connect INSITE™ electronic service tool.

Action Specification/Repair Next Step

Check for the appropriate ECM response after
30 seconds.

• Use INSITE™ electronic service tool to read
the fault codes.

Fault Code 1675 active and Fault Code 1674
inactive?

YES

Fault Code 1675 active and Fault Code 1674
inactive?

NO

STEP 2C: Check the fault codes and verify sensor condition.

Condition:

• Turn keyswitch OFF.

• Connect the exhaust gas temperature #2 sensor to the engine harness.

• Turn keyswitch ON.

• Connect INSITE™ electronic service tool.

Action Specification/Repair Next Step

Check for the appropriate circuit response after
30 seconds.

• Use INSITE™ electronic service tool to read
the fault codes.

Fault Code 1674 is active?

YES

Repair:

Replace the exhaust gas temperature #2
sensor. Refer to Procedure 019-013 in
Section 19.

2C

3A

4A

Fault Code 1674 is active?

4A

NO

Repair:

None. The removal and installation of the
connector corrected the problem.

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Page TF-24 Section TF - Troubleshooting Fault Codes

STEP 3: Check the ECM and engine harness.

STEP 3A: Inspect the ECM and engine harness connector pins.

Condition:

• Turn keyswitch OFF.

• Disconnect the engine harness from the ECM.

Action Specification/Repair Next Step

Inspect the engine harness and ECM connector
pins for the following:

• Loose connector

• Corroded pins

• Bent or broken pins

• Pushed back or expanded pins

• Moisture in or on the connector

• Missing or damaged connector seals

• Dirt or debris in or on the connector pins

• Connector shell broken

• Wire insulation damage

• Damaged connector locking tab.

Use the following procedure for general
inspection techniques. Refer to Procedure
019-361 in Section 19.

STEP 3B: Check the circuit response.

Condition:

• Turn keyswitch OFF.

• Disconnect the engine harness from the ECM.

• Turn keyswitch ON.

• Connect INSITE™ electronic service tool.

Action Specification/Repair Next Step

Dirty or damaged pins?

YES

Repair:

A damaged connection has been detected in
the ECM connector or the engine harness
connector.

Clean the connector and pins.

Repair the damaged harness, connector, or
pins if possible. Refer to Procedure 019-043
in Section 19.

Dirty or damaged pins?

NO

4A

3B

Check for the appropriate circuit response after
30 seconds.

• Use INSITE™ electronic service tool to read
the fault codes.

Fault Code 1675 is active and Fault Code
1674 is inactive?

YES

Fault Code 1675 is active and Fault Code

3C

4A

1674 is inactive?

NO

Repair:

Replace the ECM. Refer to Procedure
019-031 in Section 19.

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Section TF - Troubleshooting Fault Codes Page TF-25

STEP 3C: Check for a pin to pin short circuit in the engine harness.

Condition:

• Turn keyswitch OFF.

• Disconnect the engine harness from the ECM.

• Disconnect the exhaust gas temperature #2 sensor from the engine harness.

Action Specification/Repair Next Step

Check for a pin-to-pin short.

• Measure the resistance between the exhaust
gas temperature #2 sensor SIGNAL pin in the
engine harness ECM connector and all other
pins in the engine harness ECM connector.

Refer to the wiring diagram for connector pin
identification.

Use the following procedure for general
resistance measurement techniques. Refer to
Procedure 019-360 in Section 19.

Greater than 100K ohms?

YES

Greater than 100K ohms?

NO

Repair:

A pin-to-pin short circuit on the SIGNAL line
has been detected in the engine harness.

Repair or replace the engine harness. Refer
to Procedure 019-043 in Section 19.

3D

4A

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Page TF-26 Section TF - Troubleshooting Fault Codes

STEP 3D: Check for a pin short circuit to ground.

Condition:

• Turn keyswitch OFF.

• Disconnect the engine harness from the ECM.

• Disconnect the exhaust gas temperature #2 sensor from the engine harness.

Action Specification/Repair Next Step

Check for a pin-to-ground short.

• Measure the resistance between the exhaust
gas temperature #2 sensor SIGNAL pin in the
engine harness ECM connector and ground.

Refer to the wiring diagram for connector pin
identification.

Use the following procedure for general
resistance measurement techniques. Refer to
Procedure 019-360 in Section 19.

Greater than 100k ohms?

YES

Greater than 100k ohms?

NO

Repair:

A pin-to-ground short circuit on the SIGNAL
line has been detected in the engine
harness.

Repair or replace the engine harness. Refer
to Procedure 019-043 in Section 19.

3E

4A

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Section TF - Troubleshooting Fault Codes Page TF-27

STEP 3E: Check for an inactive fault code.

Condition:

• Connect all components.

• Turn keyswitch ON.

• Connect INSITE™ electronic service tool.

Action Specification/Repair Next Step

Check for the appropriate circuit response after
30 seconds.

• Use INSITE™ electronic service tool to read
the fault codes.

STEP 4: Clear the fault code.

STEP 4A: Disable the fault code.

Condition:

• Connect all components.

• Turn keyswitch ON.

• Connect INSITE™ electronic service tool.

Action Specification/Repair Next Step

Fault Code 16674 inactive?

YES

Repair:

None. The removal and installation of the
connector corrected the fault.

Fault Code 1674 inactive?

NO

Repair:

Troubleshooting procedures need to be
repeated from the beginning. A failure mode
should have been detected.

4A

1A

Disable the fault code.

• Start the engine and let it idle for 1 minute.

• Use INSITE™ electronic service tool to verify
the fault code is inactive.

STEP 4B: Clear the inactive fault code.

Condition:

• Connect all components.

• Turn keyswitch ON.

• Connect INSITE™ electronic service tool.

Action Specification/Repair Next Step

Clear the inactive fault codes.

• Use INSITE™ electronic service tool to erase
the inactive fault codes.

Fault Code 1674 inactive?

YES

Fault Code 1674 inactive?

NO

All fault codes cleared?

YES

All fault codes cleared?

NO

4B

1A

Repair
complete

Appropriate
troubleshooti
ng steps

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Exhaust Gas Temperature 2 Circuit — Voltage Above Norma [...] ISB, ISBe2, ISBe3, ISBe4, QSB4 [...]
Page TF-28 Section TF - Troubleshooting Fault Codes

Fault Code 1675

Exhaust Gas Temperature 2 Circuit — Voltage Above Normal, or Shorted to Low Source

CODES REASON EFFECT

Fault Code: 1675
PID(P), SID(S):
SPN: 3249
FMI: 3
Lamp: Amber
SRT:

Exhaust Gas Temperature 2
Circuit — Voltage Above Normal,
or Shorted to Low Source. High
signal voltage detected at the
catalyst outlet temperature
sensor circuit.

Default temperature used for catalyst outlet
temperature.

Circuit: Exhaust Gas Temperature 2

Circuit Description:

The catalyst outlet temperature sensor is used by the electronic control module (ECM) to monitor the engine exhaust
temperature entering the catalyst unit. The ECM monitors the voltage on the signal pin and converts this to a
temperature value.

Component Location:

The catalyst outlet temperature sensor is located in the aftertreatment system. It is located in the outlet of the
aftertreatment catalyst unit.

Shop Talk:

Catalyst outlet temperature sensor shares return wires in the engine harness with other sensors. A shorted return can
cause multiple fault codes to be active.

Possible causes of this fault code include:

• Open return circuit in the harness, connectors, or sensor.

• Open signal circuit or shorted to a voltage source.

On-Board Diagnostics (OBD) Information (Euro 4 Certified Engines):

• The ECM illuminates the malfunction indicator lamp (MIL) when the diagnostic runs and fails.

• The ECM turns OFF the malfunction indicator lamp (MIL) after 3 consecutive ignition cycles that the diagnostic runs
and does not fail. The MIL lamp and fault code can also be cleared using the INSITE™ service tool.

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ISB, ISBe2, ISBe3, ISBe4, QSB4 [...] Exhaust Gas Temperature 2 Circuit — Voltage Above Norma [...]
Section TF - Troubleshooting Fault Codes Page TF-29

• The fault code will be cleared from memory after 40 consecutive drive cycles where the diagnostic runs and passes.

On-Board Diagnostics (OBD) Information (Euro 4 Stage 1+ Certified Engines):

• The ECM illuminates the malfunction indicator lamp (MIL) when the diagnostic runs and fails.

• An engine torque derate will be activated after 50 hours of engine operation with the fault code active.

• The ECM turns OFF the malfunction indicator lamp (MIL) after 1 ignition cycle that the diagnostic runs and does not
fail. The MIL lamp cannot be cleared using the INSITE™ service tool.

• The fault code will be cleared from memory after 400 days or 9600 hours of engine operation.

Refer to Troubleshooting Fault Code t05-1675

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ISB, ISBe2, ISBe3, ISBe4, QSB4 [...]

Page TF-30 Section TF - Troubleshooting Fault Codes

FAULT CODE 1675 - Exhaust Gas Temperature 2 Circuit - Voltage Above

Normal, or Shorted to Low Source

TROUBLESHOOTING SUMMARY

CAUTION
To reduce the possibility of damaging a new ECM, all other active fault codes must be investigated prior to
replacing the ECM.

CAUTION
To reduce the possibility of pin and harness damage, use the following test leads when taking a
measurement: Part Number 3822758 - male Deutsch™/AMP™/Metri-Pack™ test lead and Part Number 3822917

- female Deutsch™/AMP™/Metri-Pack™ test lead.

STEPS

SPECIFICATIONS SRT CODE

STEP 1: Check the fault codes.

STEP 1A: Check for an inactive fault code. Fault Code 1675 inactive?

STEP 2: Check the exhaust gas temperature #2 sensor and circuit.

STEP 2A: Inspect the exhaust gas

temperature #2 sensor and
connector pins.

STEP 2B: Check the circuit response. Fault Code 1674 is active and

STEP 2C: Check the fault codes and verify

sensor condition.

Dirty or damaged pins?

fault code 1675 is inactive?

Fault Code 1675 is active?

STEP 3: Check the ECM and engine harness.

STEP 3A: Inspect the ECM and engine

harness connector pins.

STEP 3B: Check the circuit response. Fault Code 1674 is active and

STEP 3C: Check for an open circuit in the

engine harness.

STEP 3C-1: Check for an open circuit in

the engine harness.

STEP 3D: Check for a pin-to-pin short

circuit in the engine harness.

STEP 3E: Check for an inactive fault code. Fault Code 1675 inactive?

Dirty or damaged pins?

Fault Code 1675 is inactive?

Less than 10 ohms?

Less than 10 ohms?

Greater than 100K ohms?

STEP 4: Clear the fault code.

STEP 4A: Disable the fault code. Fault Code 1675 inactive?

STEP 4B: Clear the inactive fault codes. All fault codes cleared?

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Section TF - Troubleshooting Fault Codes Page TF-31

TROUBLESHOOTING STEP

STEP 1: Check the fault codes.

STEP 1A: Check for an inactive fault code.

Condition:

• Turn keyswitch ON.

• Connect INSITE™ electronic service tool.

Action Specification/Repair Next Step

Check for an inactive fault code.

• Use INSITE™ electronic service tool to read
the fault codes.

Fault Code 1675 inactive?

YES

Fault Code 1675 inactive?

NO

STEP 2: Check the exhaust gas temperature #2 sensor and circuit.

STEP 2A: Inspect the exhaust gas temperature #2 sensor and connector pins.

Condition:

• Turn keyswitch OFF.

• Disconnect the exhaust gas temperature #2 sensor from the engine harness.

Action Specification/Repair Next Step

Inspect the engine harness and exhaust gas
temperature #2 sensor connector pins for the
following:

• Loose connector

• Corroded pins

• Bent or broken pins

• Pushed back or expanded pins

• Moisture in or on the connector

• Missing or damaged connector seals

• Dirt or debris in or on the connector pins

• Connector shell broken

• Wire insulation damage

• Damaged connector locking tab.

Use the following procedure for general
inspection techniques. Refer to Procedure
019-361 in Section 19.

Dirty or damaged pins?

YES

Repair:

A damaged connection has been detected in
the sensor or harness connector.

Clean the connector and pins.

Repair the damaged harness, connector, or
pins if possible. Refer to Procedure 019-071
in Section 19.

Dirty or damaged pins?

NO

Use the
following
procedure for
an inactive or
intermittent
fault code.
Refer to
Procedure
019-362 in
Section 19.

2A

4A

2B

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Page TF-32 Section TF - Troubleshooting Fault Codes

STEP 2B: Check the circuit response.

Condition:

• Turn keyswitch OFF.

• Disconnect the exhaust gas temperature #2 sensor from the engine harness.

• Turn keyswitch ON.

• Connect INSITE™ electronic service tool.

Action Specification/Repair Next Step

Place a jumper wire between the exhaust gas
temperatue #2 SIGNAL pin and the exhaust gas
temperature #2 RETURN pin at the sensor
connector of the engine harness.

• Refer to the wiring diagram for connector pin
identification.

Fault Code 1674 is active and Fault Code
1675 is inactive?

YES

Fault Code 1674 is active and Fault Code
1675 is inactive?

NO

2C

3A

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Section TF - Troubleshooting Fault Codes Page TF-33

STEP 2C: Check the fault codes and verify sensor condition.

Condition:

• Turn keyswitch OFF.

• Connect the exhaust gas temperature #2 sensor to the engine harness.

• Turn keyswitch ON.

• Connect INSITE™ electronic service tool.

Action Specification/Repair Next Step

Check for the appropriate circuit response after
30 seconds.

• Use INSITE™ electronic service tool to read
the fault codes.

Fault Code 1675 is active?

YES

Repair:

A damaged exhaust gas temperature #2
sensor has been detected.

Replace the exhaust gas temperature #2
sensor. Refer to Procedure 019-013 in
Section 19.

Fault Code 1675 is active?

NO

Repair:

None. The removal and installation of the
connector corrected the problem.

STEP 3: Check the ECM and engine harness.

STEP 3A: Inspect the ECM and engine harness connector pins.

Condition:

• Turn keyswitch OFF.

• Disconnect the engine harness from the ECM connector.

4A

4A

Action Specification/Repair Next Step

Inspect the engine harness and ECM connector
pins for the following:

• Loose connector

• Corroded pins

• Bent or broken pins

• Pushed back or expanded pins

• Moisture in or on the connector

• Missing or damaged connector seals

• Dirt or debris in or on the connector pins

• Connector shell broken

• Wire insulation damage

• Damaged connector locking tab.

Use the following procedure for general
inspection techniques. Refer to Procedure
019-361 in Section 19.

Dirty or damaged pins?

YES

Repair:

A damaged connection has been detected in
the ECM connector or the engine harness
connector.

Clean the connector and pins.

Repair the damaged harness, connector, or
pins if possible. Refer to Procedure 019-043
in Section 19.

Dirty or damaged pins?

NO

4A

3B

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Page TF-34 Section TF - Troubleshooting Fault Codes

STEP 3B: Check the circuit response.

Condition:

• Turn keyswitch OFF.

• Disconnect the engine harness from the ECM.

• Turn keyswitch ON.

• Connect INSITE™ electronic service tool.

Action Specification/Repair Next Step

Place a jumper wire between the exhaust gas
temperature #2 sensor SIGNAL pin and the
exhaust gas temperature #2 sensor RETURN pin
at the ECM connector.

• Check for the appropriate circuit response
after 30 seconds.

• Use INSITE™ electronic service tool to read
the fault codes.

Refer to the wiring diagram for connector pin
identification.

Fault Code 1674 active and Fault Code 1675
is inactive?

YES

Fault Code 1674 active and Fault Code 1675
is inactive?

NO

Repair:

Replace the ECM. Refer to Procedure
019-031 in Section 19.

3C

4A

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Section TF - Troubleshooting Fault Codes Page TF-35

STEP 3C: Check for an open circuit in the engine harness.

Condition:

• Turn keyswitch OFF.

• Disconnect the engine harness from the ECM.

• Disconnect the exhaust gas temperature #2 sensor from the engine harness.

Action Specification/Repair Next Step

Check for an open circuit.

• Measure the resistance between the engine
harness ECM connector exhaust gas
temperature #2 sensor RETURN pin and the
engine harness exhaust gas temperature #2
sensor connector RETURN pin.

Refer to the wiring diagram for connector pin
identification.

Use the following procedure for general
resistance measurement techniques. Refer to
Procedure 019-360 in Section 19.

Less than 10 ohms?

YES

Less than 10 ohms?

NO

Repair:

An open RETURN circuit has been detected
in the engine harness.

Repair or replace the engine harness. Refer
to Procedure 019-043 in Section 19.

3C-1

4A

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Page TF-36 Section TF - Troubleshooting Fault Codes

STEP 3C-1: Check for an open circuit in the engine harness.

Condition:

• Turn keyswitch OFF.

• Disconnect the engine harness from the ECM.

• Disconnect the exhaust gas temperature #2 sensor from the engine harness.

Action Specification/Repair Next Step

Check for an open circuit.

• Measure the resistance between the engine
harness ECM connector exhaust gas
temperature #2 sensor SIGNAL pin and the
engine harness exhaust gas temperature #2
sensor connector SIGNAL pin.

Refer to the wiring diagram for connector pin
identification.

Use the following procedure for general
resistance measurement techniques. Refer to
Procedure 019-360 in Section 19.

Less than 10 ohms?

YES

Less than 10 ohms?

NO

Repair:

An open SIGNAL circuit has been detected
in the engine harness.

Repair or replace the engine harness. Refer
to Procedure 019-043 in Section 19.

3D

4A

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Section TF - Troubleshooting Fault Codes Page TF-37

STEP 3D: Check for a pin-to-pin short circuit in the engine harness.

Condition:

• Turn keyswitch OFF.

• Disconnect the engine harness from the ECM.

• Disconnect the exhaust gas temperature #2 sensor from the engine harness.

Action Specification/Repair Next Step

Check for a pin-to-pin short.

• Measure the resistance between the exhaust
gas temperature #2 sensor SIGNAL pin in the
engine harness ECM connector and all other
pins in the engine harness ECM connector.

Refer to the wiring diagram for connector pin
identification.

Use the following procedure for general
resistance measurement techniques. Refer to
Procedure 019-360 in Section 19.

Greater than 100K ohms?

YES

Greater than 100K ohms?

NO

Repair:

A pin-to-pin short circuit on the SIGNAL line
has been detected in the engine harness.

Repair or replace the engine harness. Refer
to Procedure 019-043 in Section 19.

3E

4A

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Page TF-38 Section TF - Troubleshooting Fault Codes

STEP 3E: Check for an inactive fault code.

Condition:

• Connect all components.

• Turn keyswitch ON.

• Connect INSITE™ electronic service tool.

Action Specification/Repair Next Step

Check for the appropriate circuit response after
30 seconds.

• Use INSITE™ electronic service tool to read
the fault codes.

STEP 4: Clear the fault code.

STEP 4A: Disable the fault code.

Condition:

• Connect all components.

• Turn keyswitch ON.

• Connect INSITE™ electronic service tool.

Action Specification/Repair Next Step

Fault Code 1675 inactive?

YES

Repair:

None. The removal and installation of the
connector corrected the fault.

Fault Code 1675 inactive?

NO

Repair:

Troubleshooting procedures need to be
repeated from the beginning. A failure mode
should have been detected.

4A

1A

Disable the fault code.

• Start the engine and let it idle for 1 minute.

• Use INSITE™ electronic service tool to verify
the fault code is inactive.

STEP 4B: Clear the inactive fault codes.

Condition:

• Connect all components.

• Turn keyswitch ON.

• Connect INSITE™ electronic service tool.

Action Specification/Repair Next Step

Clear the inactive fault codes.

• Using INSITE™ electronic service tool erase
the inactive fault codes.

Fault Code 1675 inactive?

YES

Fault Code 1675 inactive?

NO

All fault codes cleared?

YES

All fault codes cleared?

NO

4B

1A

Repair
complete

Appropriate
troubleshooti
ng steps

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ISB, ISBe2, ISBe3, ISBe4, QSB4 [...] Exhaust Gas Temperature 2— Data Erratic, Intermittent, [...]
Section TF - Troubleshooting Fault Codes Page TF-39

Fault Code 1676

Exhaust Gas Temperature 2— Data Erratic, Intermittent, or Incorrect

CODES REASON EFFECT

Fault Code: 1676
PID(P), SID(S):
SPN: 3249
FMI: 2
Lamp: Amber
SRT:

Exhaust Gas Temperature 2 —
Data Erratic, Intermittent, or
Incorrect. The exhaust gas
temperature #2 sensor is not
changing with engine operating
conditions.

Default temperature value used for exhaust
gas temperature #2.

Circuit: Exhaust Gas Temperature 2

Circuit Description:

The exhaust gas temperature #2 sensor is used by the electronic control module (ECM) to monitor the engine exhaust
temperature entering the catalyst unit. The ECM monitors the voltage on the signal pin and converts this to a
temperature value. This sensor is also called the catalyst outlet temperature sensor.

Component Location:

The exhaust gas temperature #2 sensor is located in the aftertreatment system. It is located between the turbocharger
outlet and the catalyst unit outlet in the exhaust system.

Shop Talk:

This diagnostic runs when the exhaust gas temperature sensors are compared to other engine temperatures during
engine operation. The engine coolant temperature must be above 140°F before the diagnostic will run. If the value of
the exhaust gas temperature #2 does not match the engine operating conditions, this fault code is logged.

Possible causes of this fault code include:

• Stuck in-range exhaust gas temperature #2 sensor

• High resistance in the exhaust gas temperature #2 sensor signal or return lines.

On-Board Diagnostics (OBD) Information:

• The ECM illuminates the malfunction indicator lamp (MIL) on the second consecutive ignition cycle that the
diagnostic runs and fails.

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Exhaust Gas Temperature 2— Data Erratic, Intermittent, [...] ISB, ISBe2, ISBe3, ISBe4, QSB4 [...]
Page TF-40 Section TF - Troubleshooting Fault Codes

• The ECM turns OFF the malfunction indicator lamp (MIL) after 3 consecutive ignition cycles that the diagnostic runs
and does not fail. The MIL lamp and fault code can also be cleared using the INSITE™ service tool.

• The fault code will be cleared from memory after 40 consecutive drive cycles where the diagnostic runs and passes.

Refer to Troubleshooting Fault Code t05-1676

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ISB, ISBe2, ISBe3, ISBe4, QSB4 [...]
Section TF - Troubleshooting Fault Codes Page TF-41

FAULT CODE 1676 - Exhaust Gas Temperature 2 - Data Erratic, Intermittent, or

Incorrect

TROUBLESHOOTING SUMMARY

CAUTION
To reduce the possibility of damaging a new ECM, all other active fault codes must be investigated prior to
replacing the ECM.

CAUTION
To reduce the possibility of pin and harness damage, use the following test leads when taking a
measurement: Part Number 3822758 - male Deutsch™/AMP™/Metri-Pack™ test lead and Part Number 3822917

- female Deutsch™/AMP™/Metri-Pack™ test lead.

STEPS

SPECIFICATIONS SRT CODE

STEP 1: Check for sensor circuit fault codes.

STEP 1A: Check for Fault Codes 1674 and

1675.

Fault Code 1674 or 1675 is
active?

STEP 2: Check the exhaust gas temperature #2 sensor and circuit.

STEP 2A: Inspect the exhaust gas

temperature #2 sensor and
connector pins.

STEP 2B: Check the circuit response. Fault Code 1675 active?

Dirty or damaged pins?

STEP 3: Check the ECM and engine harness.

STEP 3A: Inspect the ECM and engine

harness connector pins.

STEP 3B: Check the circuit response. Fault Code 1675 active?

Dirty or damaged pins?

STEP 4: Clear the fault codes.

STEP 4A: Verify the repair Catalyst Inlet Temperature and

Catalyst Outlet Temperature
reading within 13.9°C or 25°F of
each other?

STEP 4B: Clear the fault codes. All fault codes cleared?

TROUBLESHOOTING STEP

STEP 1: Check for sensor circuit fault codes.

STEP 1A: Check for Fault Codes 1674 and 1675.

Condition:

• Turn keyswitch ON.

• Connect INSITE™ electronic service tool.

Action Specification/Repair Next Step

Check for an active fault codes.

• Use INSITE™ electronic service tool to read
the fault codes.

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Fault Code 1674 or 1675 is active?

YES

Fault Code 1674 or 1675 is active?

NO

Fault Code
1674 or 1675
troubleshooti
ng tree.

2A

ISB, ISBe2, ISBe3, ISBe4, QSB4 [...]

Page TF-42 Section TF - Troubleshooting Fault Codes

STEP 2: Check the exhaust gas temperature #2 sensor and circuit.

STEP 2A: Inspect the exhaust gas temperature #2 sensor and connector pins.

Condition:

• Turn keyswitch OFF.

• Disconnect the exhaust gas temperature #2 sensor from the engine harness.

Action Specification/Repair Next Step

Inspect the engine harness and exhaust gas
temperature #2 sensor connector pins for the
following:

• Loose connector

• Corroded pins

• Bent or broken pins

Dirty or damaged pins?

YES

Repair:

A damaged connection has been detected in
the sensor or harness connector.

• Pushed back or expanded pins

• Moisture in or on the connector

• Missing or damaged connector seals

• Dirt or debris in or on the connector pins

• Connector shell broken

Clean the connector and pins.

Repair the damaged harness, connector, or
pins if possible. Refer to Procedure 019-071
in Section 19.

• Wire insulation damage

• Damaged connector locking tab.

Use the following procedure for general
inspection techniques. Refer to Procedure

Dirty or damaged pins?

NO

019-361 in Section 19.

STEP 2B: Check the circuit response.

Condition:

• Turn keyswitch OFF.

• Disconnect the exhaust gas temperature #2 sensor from the engine harness.

• Turn keyswitch ON.

• Connect INSITE™ electronic service tool.

• Engine coolant temperature must be above 60°C [140°F].

4A

2B

Action Specification/Repair Next Step

Check for the appropriate ECM response after
30 seconds.

• Use INSITE™ electronic service tool to read
the fault codes.

Fault Code 1675 active?

YES

Fault Code 1675 active?

NO

Repair:

Replace the exhaust gas temperature #2
sensor. Refer to Procedure 019-013 in
Section 19.

3A

4A

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ISB, ISBe2, ISBe3, ISBe4, QSB4 [...]
Section TF - Troubleshooting Fault Codes Page TF-43

STEP 3: Check the ECM and engine harness.

STEP 3A: Inspect the ECM and engine harness connector pins.

Condition:

• Turn keyswitch OFF.

• Disconnect the engine harness from the ECM connector.

Action Specification/Repair Next Step

Inspect the engine harness and ECM connector
pins for the following:

• Loose connector

• Corroded pins

• Bent or broken pins

• Pushed back or expanded pins

• Moisture in or on the connector

Dirty or damaged pins?

YES

Repair:

A damaged connection has been detected in
the ECM connector or the engine harness
connector.

• Missing or damaged connector seals

• Dirt or debris in or on the connector pins

• Connector shell broken

• Wire insulation damage

• Damaged connector locking tab.

Clean the connector and pins.

Repair the damaged harness, connector, or
pins if possible. Refer to Procedure 019-043
in Section 19.

Use the following procedure for general
inspection techniques. Refer to Procedure
019-361 in Section 19.

Dirty or damaged pins?

NO

STEP 3B: Check the circuit response.

Condition:

• Turn keyswitch OFF.

• Disconnect the engine harness from the ECM.

• Turn keyswitch ON.

• Connect INSITE™ electronic service tool.

• Engine coolant temperature must be above 60°C [140°F].

4A

3B

Action Specification/Repair Next Step

Check for the appropriate circuit response after
30 seconds.

• Use INSITE™ electronic service tool to read
the fault codes.

Fault Code 1675 is active?

YES

Repair:

High resistance or a short circuit has been
detected in the engine harness.

Repair or replace the engine harness. Refer
to Procedure 019-043 in Section 19.

Fault Code 1675 is active?

NO

Repair:

Replace the ECM. Refer to Procedure
019-031 in Section 19.

4A

4A

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ISB, ISBe2, ISBe3, ISBe4, QSB4 [...]

Page TF-44 Section TF - Troubleshooting Fault Codes

STEP 4: Clear the fault code.

STEP 4A: Verify the repair.

Condition:

• Connect all components.

• Turn keyswitch ON.

• Connect INSITE™ electronic service tool.

Action Specification/Repair Next Step

Start the INSITE™ Data Monitor/Logger.

• Compare the INSITE™ electronic service tool
reading for Catalyst Inlet Temperature and
Catalyst Outlet Temperature.

STEP 4B: Clear the fault codes.

Condition:

• Connect all components.

• Turn keyswitch ON.

• Connect INSITE™ electronic service tool.

Action Specification/Repair Next Step

Clear the fault codes.

• Use INSITE™ electronic service tool to erase
all active and inactive fault codes.

Catalyst Inlet Temperature and Catalyst
Outlet Temperature reading within 13.9°C or
25°F of each other?

YES

Catalyst Inlet Temperature and Catalyst
Outlet Temperature reading within 13.9°C or
25°F of each other?

NO

All fault codes cleared?

YES

All fault codes cleared?

NO

4B

1A

Repair
complete

Appropriate
troubleshooti
ng steps

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ISB, ISBe2, ISBe3, ISBe4, QSB4 [...] Catalyst Tank Temperature — Voltage Below Normal, or Sh [...]
Section TF - Troubleshooting Fault Codes Page TF-45

Fault Code 1677

Catalyst Tank Temperature — Voltage Below Normal, or Shorted to Low Source

CODES REASON EFFECT

Fault Code: 1677
PID(P), SID(S):
SPN: 3031
FMI: 4
Lamp: Amber
SRT:

Catalyst Tank Temperature —
Voltage Below Normal, or
Shorted to Low Source. Low
signal voltage detected at the
catalyst solution temperature
sensor circuit.

Default temperature used for catalyst solution
temperature.

Circuit: Catalyst Solution Temperature Sensor

Circuit Description:

The catalyst solution temperature sensor is used by the electronic control module (ECM) to monitor the temperature of
the catalyst solution inside the catalyst tank. The ECM monitors the voltage on the signal pin and converts this to a
temperature value.

Component Location:

The catalyst solution temperature sensor is located in the catalyst tank. The tank is mounted by the OEM. For more
information, contact the OEM service manual.

Shop Talk:

The catalyst solution temperature sensor shares return wires in the engine harness with other sensors. A shorted
return can cause multiple fault codes to be active. Before troubleshooting Fault Code 1677, check for multiple fault
codes.

Possible causes of this fault code include:

• Signal shorted to ground in the harness

• Signal shorted to return or ground in the sensor.

On-Board Diagnostics (OBD) Information (Euro 4 Certified Engines):

• The ECM illuminates the malfunction indicator lamp (MIL) when the diagnostic runs and fails.

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Catalyst Tank Temperature — Voltage Below Normal, or Sh [...] ISB, ISBe2, ISBe3, ISBe4, QSB4 [...]
Page TF-46 Section TF - Troubleshooting Fault Codes

• The ECM turns OFF the malfunction indicator lamp (MIL) after 3 consecutive ignition cycles that the diagnostic runs
and does not fail. The MIL lamp and fault code can also be cleared using the INSITE™ service tool.

• The fault code will be cleared from memory after 40 consecutive drive cycles where the diagnostic runs and passes.

On-Board Diagnostics (OBD) Information (Euro 4 Stage 1+ Certified Engines):

• The ECM illuminates the malfunction indicator lamp (MIL) when the diagnostic runs and fails.

• An engine torque derate will be activated after 50 hours of engine operation with the fault code active.

• The ECM turns OFF the malfunction indicator lamp (MIL) after 1 ignition cycle that the diagnostic runs and does not
fail. The MIL lamp cannot be cleared using the INSITE™ service tool.

• The fault code will be cleared from memory after 400 days or 9600 hours of engine operation.

Refer to Troubleshooting Fault Code t05-1677

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ISB, ISBe2, ISBe3, ISBe4, QSB4 [...]
Section TF - Troubleshooting Fault Codes Page TF-47

FAULT CODE 1677 - Catalyst Tank Temperature - Voltage Below Normal, or

Shorted to Low Source

TROUBLESHOOTING SUMMARY

CAUTION
To reduce the possibility of damaging a new ECM, all other active fault codes must be investigated prior to
replacing the ECM.

CAUTION
To reduce the possibility of pin and harness damage, use the following test leads when taking a
measurement: Part Number 3822758 - male Deutsch™/AMP™/Metri-Pack™ test lead and Part Number 3822917

- female Deutsch™/AMP™/Metri-Pack™ test lead.

STEPS

SPECIFICATIONS SRT CODE

STEP 1: Check the fault codes.

STEP 1A: Check for an inactive fault code. Fault Code 1677 inactive?

STEP 2: Check the catalyst solution temperature sensor and circuit.

STEP 2A: Inspect the catalyst solution

temperature sensor and
connector pins.

STEP 2B: Check the circuit response. Fault Code 1678 active and fault

STEP 2C: Check the fault codes and verify

sensor condition.

Dirty or damaged pins?

code 1677 inactive?

Fault Code 1677 is active?

STEP 3: Check the ECM and engine harness.

STEP 3A: Inspect the ECM and engine

harness connector pins.

STEP 3B: Check the circuit response. Fault Code 1678 active and Fault

STEP 3C: Check for a pin-to-pin short

circuit in the engine harness.

STEP 3D: Check for a pin short circuit to

ground.

STEP 3E: Check for an inactive fault code. Fault Code 1677 inactive?

Dirty or damaged pins?

Code 1677 inactive?

Greater than 100K ohms?

Greater than 100K ohms?

STEP 4: Clear the fault code.

STEP 4A: Disable the fault code. Fault Code 1677 inactive?

STEP 4B: Clear the inactive fault codes. All fault codes cleared?

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ISB, ISBe2, ISBe3, ISBe4, QSB4 [...]

Page TF-48 Section TF - Troubleshooting Fault Codes

TROUBLESHOOTING STEP

STEP 1: Check the fault codes.

STEP 1A: Check for an inactive fault code.

Condition:

• Turn keyswitch ON.

• Connect INSITE™ electronic service tool.

Action Specification/Repair Next Step

Check for an inactive fault code.

• Use INSITE™ to read the fault codes.

Fault Code 1677 inactive?

YES

Fault Code 1677 inactive?

NO

STEP 2: Check the catalyst solution temperature sensor and circuit.

STEP 2A: Inspect the catalyst solution temperature sensor and connector pins.

Condition:

• Turn keyswitch OFF.

• Disconnect the catalyst solution temperature sensor from the engine harness.

Action Specification/Repair Next Step

Inspect the engine harness and catalyst solution
temperature sensor connector pins for the
following:

• Loose connector

• Corroded pins

• Bent or broken pins

• Pushed back or expanded pins

• Moisture in or on the connector

• Missing or damaged connector seals

• Dirt or debris in or on the connector pins

• Connector shell broken

• Wire insulation damage

• Damaged connector locking tab.

Use the following procedure for general
inspection techniques. Refer to Procedure
019-361 in Section 19.

Dirty or damaged pins?

YES

Repair:

A damaged connection has been detected in
the sensor or harness connector.

Clean the connector and pins.

Repair the damaged harness, connector, or
pins if possible. Refer to Procedure 019-071
in Section 19.

Dirty or damaged pins?

NO

Use the
following
procedure for
an inactive or
intermittent
fault code.
Refer to
Procedure
019-362 in
Section 19.

2A

4A

2B

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ISB, ISBe2, ISBe3, ISBe4, QSB4 [...]
Section TF - Troubleshooting Fault Codes Page TF-49

STEP 2B: Check the circuit response.

Condition:

• Turn keyswitch OFF.

• Disconnect the catalyst solution temperature sensor from the engine harness.

• Turn keyswitch ON.

• Connect INSITE™ electronic service tool.

Action Specification/Repair Next Step

Check for the appropriate ECM response after
30 seconds.

• Use INSITE™ electronic service tool to read
the fault codes.

Fault code 1678 active and Fault Code 1677
inactive?

YES

Fault code 1678 active and Fault Code 1677
inactive?

NO

STEP 2C: Check the fault codes and verify sensor condition.

Condition:

• Turn keyswitch OFF.

• Connect the catalyst solution temperature sensor to the engine harness.

• Turn keyswitch ON.

• Connect INSITE™ electronic service tool.

Action Specification/Repair Next Step

Check for the appropriate circuit response after
30 seconds.

• Use INSITE™ electronic service tool to read
the fault codes.

Fault Code 1677 is active?

YES

Repair:

Replace the catalyst solution temperature
sensor. Refer to OEM service manual.

2C

3A

4A

Fault Code 1677 is active?

4A

NO

Repair:

None. The removal and installation of the
connector corrected the fault.

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ISB, ISBe2, ISBe3, ISBe4, QSB4 [...]

Page TF-50 Section TF - Troubleshooting Fault Codes

STEP 3: Check the ECM and engine harness.

STEP 3A: Inspect the ECM and engine harness connector pins.

Condition:

• Turn keyswitch OFF.

• Disconnect the engine harness from the ECM.

Action Specification/Repair Next Step

Inspect the engine harness and ECM connector
pins for the following:

• Loose connector

• Corroded pins

• Bent or broken pins

• Pushed back or expanded pins

• Moisture in or on the connector

• Missing or damaged connector seals

• Dirt or debris in or on the connector pins

• Connector shell broken

• Wire insulation damage

• Damaged connector locking tab.

Use the following procedure for general
inspection techniques. Refer to Procedure
019-361 in Section 19.

STEP 3B: Check the circuit response.

Condition:

• Turn keyswitch OFF.

• Disconnect the engine harness from the ECM.

• Turn keyswitch ON.

• Connect INSITE™ electronic service tool.

Action Specification/Repair Next Step

Dirty or damaged pins?

YES

Repair:

A damaged connection has been detected in
the ECM connector or the engine harness
connector.

Clean the connector and pins.

Repair the damaged harness, connector, or
pins if possible. Refer to Procedure 019-043
in Section 19.

Dirty or damaged pins?

NO

4A

3B

Check for the appropriate circuit response after
30 seconds.

• Use INSITE™ electronic service tool to read
the fault codes.

Fault Code 1678 is active and Fault Code
1677 is inactive?

YES

Fault Code 1678 is active and Fault Code

3C

4A

1677 is inactive?

NO

Repair:

Replace the ECM. Refer to Procedure
019-031 in Section 19.

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ISB, ISBe2, ISBe3, ISBe4, QSB4 [...]
Section TF - Troubleshooting Fault Codes Page TF-51

STEP 3C: Check for a pin-to-pin short circuit in the engine harness.

Condition:

• Turn keyswitch OFF.

• Disconnect the engine harness from the ECM.

• Disconnect the catalyst solution temperature sensor from the engine harness.

Action Specification/Repair Next Step

Check for a pin-to-pin short.

• Measure the resistance between the catalyst
solution temperature sensor SIGNAL pin in the
engine harness ECM connector and all other
pins in the engine harness ECM connector.

Refer to the wiring diagram for connector pin
identification.

Use the following procedure for general
resistance measurement techniques. Refer to
Procedure 019-360 in Section 19.

Greater than 100K ohms?

YES

Greater than 100K ohms?

NO

Repair:

A pin-to-pin short circuit on the SIGNAL line
has been detected in the engine harness.

Repair or replace the engine harness. Refer
to Procedure 019-043 in Section 19.

3D

4A

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ISB, ISBe2, ISBe3, ISBe4, QSB4 [...]

Page TF-52 Section TF - Troubleshooting Fault Codes

STEP 3D: Check for a pin short circuit to ground.

Condition:

• Turn keyswitch OFF.

• Disconnect the engine harness from the ECM.

• Disconnect the catalyst solution sensor from the engine harness.

Action Specification/Repair Next Step

Check for a pin-to-ground short.

• Measure the resistance between the catalyst
solution sensor SIGNAL pin in the engine
harness ECM connector and ground.

Refer to the wiring diagram for connector pin
identification.

Use the following procedure for general
resistance measurement techniques. Refer to
Procedure 019-360 in Section 19.

Greater than 100k ohms?

YES

Greater than 100k ohms?

NO

Repair:

A pin-to-ground short circuit on the SIGNAL
line has been detected in the engine
harness.

Repair or replace the engine harness. Refer
to Procedure 019-043 in Section 19.

3E

4A

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ISB, ISBe2, ISBe3, ISBe4, QSB4 [...]
Section TF - Troubleshooting Fault Codes Page TF-53

STEP 3E: Check for an inactive fault code.

Condition:

• Connect all components.

• Turn keyswitch ON.

• Connect INSITE™ electronic service tool.

Action Specification/Repair Next Step

Check for the appropriate circuit response after
30 seconds.

• Use INSITE™ electronic service tool to read
the fault codes.

STEP 4: Clear the fault code.

STEP 4A: Disable the fault code.

Condition:

• Connect all components.

• Turn keyswitch ON.

• Connect INSITE™ electronic service tool.

Action Specification/Repair Next Step

Fault Code 1677 inactive?

YES

Repair:

None. The removal and installation of the
connector corrected the fault.

Fault Code 1677 inactive?

NO

Repair:

Troubleshooting procedures need to be
repeated from the beginning. A failure mode
should have been detected.

4A

1A

Disable the fault code.

• Start the engine and let it idle for 1 minute.

• Use INSITE™ electronic service tool to verify
the fault code is inactive.

STEP 4B: Clear the inactive fault codes.

Condition:

• Connect all components.

• Turn keyswitch ON.

• Connect INSITE™ electronic service tool.

Action Specification/Repair Next Step

Clear the inactive fault codes.

• Use INSITE™ electronic service tool to erase
the inactive fault codes.

Fault Code 1677 inactive?

YES

Fault Code 1677 inactive?

NO

All fault codes cleared?

YES

All fault codes cleared?

NO

4B

1A

Repair
complete

Appropriate
troubleshooti
ng steps

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Catalyst Tank Temperature — Voltage Above Normal, or Sh [...] ISB, ISBe2, ISBe3, ISBe4, QSB4 [...]
Page TF-54 Section TF - Troubleshooting Fault Codes

Fault Code 1678

Catalyst Tank Temperature — Voltage Above Normal, or Shorted to High Source

CODES REASON EFFECT

Fault Code: 1678
PID(P), SID(S):
SPN: 3031
FMI: 3
Lamp: Amber
SRT:

Catalyst Tank Temperature —
Voltage Above Normal, or
Shorted to High Source. High
signal voltage or open circuit
detected at the catalyst tank
temperature sensor circuit

Default temperature value used for catalyst
tank temperature.

Circuit: Catalyst Tank Temperature Sensor

Circuit Description:

The catalyst solution temperature sensor is used by the electronic control module (ECM) to monitor the temperature of
the catalyst solution inside the catalyst tank. The ECM monitors the voltage on the signal pin and converts this to a
temperature value.

Component Location:

The catalyst solution temperature sensor is located in the catalyst tank. The tank is mounted by the OEM. For more
information, contact the OEM service manual.

Shop Talk:

The catalyst solution temperature sensor shares return wires in the engine harness with other sensors. An open return
can cause multiple fault codes to be active.

Possible causes of this fault code include:

• Open return circuit in the harness, connectors, or sensor.

• Open signal circuit or shorted to a voltage source.

On-Board Diagnostics (OBD) Information (Euro 4 Certified Engines):

• The ECM illuminates the malfunction indicator lamp (MIL) when the diagnostic runs and fails.

• The ECM turns OFF the malfunction indicator lamp (MIL) after 3 consecutive ignition cycles that the diagnostic runs
and does not fail. The MIL lamp and fault code can also be cleared using the INSITE™ service tool.

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ISB, ISBe2, ISBe3, ISBe4, QSB4 [...] Catalyst Tank Temperature — Voltage Above Normal, or Sh [...]
Section TF - Troubleshooting Fault Codes Page TF-55

• The fault code will be cleared from memory after 40 consecutive drive cycles where the diagnostic runs and passes.

On-Board Diagnostics (OBD) Information (Euro 4 Stage 1+ Certified Engines):

• The ECM illuminates the malfunction indicator lamp (MIL) when the diagnostic runs and fails.

• An engine torque derate will be activated after 50 hours of engine operation with the fault code active.

• The ECM turns OFF the malfunction indicator lamp (MIL) after 1 ignition cycle that the diagnostic runs and does not
fail. The MIL lamp cannot be cleared using the INSITE™ service tool.

• The fault code will be cleared from memory after 400 days or 9600 hours of engine operation.

Refer to Troubleshooting Fault Code t05-1678

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ISB, ISBe2, ISBe3, ISBe4, QSB4 [...]

Page TF-56 Section TF - Troubleshooting Fault Codes

FAULT CODE 1678 - Catalyst Tank Temperature - Voltage Above Normal, or

Shorted to High Source

TROUBLESHOOTING SUMMARY

CAUTION
To reduce the possibility of damaging a new ECM, all other active fault codes must be investigated prior to
replacing the ECM.

CAUTION
To reduce the possibility of pin and harness damage, use the following test leads when taking a
measurement: Part Number 3822758 - male Deutsch™/AMP™/Metri-Pack™ test lead and Part Number 3822917

- female Deutsch™/AMP™/Metri-Pack™ test lead.

STEPS

SPECIFICATIONS SRT CODE

STEP 1: Check the fault codes.

STEP 1A: Check for an inactive fault code. Fault Code 1678 inactive?

STEP 2: Check the catalyst solution temperature sensor and circuit.

STEP 2A: Inspect the catalyst solution

temperature sensor and
connector pins.

STEP 2B: Check the sensor resistance. 180 ohms to 160k ohms?

STEP 2C: Check the fault codes and verify

sensor condition.

Dirty or damaged pins?

Fault Code 1678 is active?

STEP 3: Check the ECM and engine harness.

STEP 3A: Inspect the ECM and engine

harness connector pins.

STEP 3B: Check the circuit response. Fault Code 1677 is active and

STEP 3C: Check for an open circuit in the

engine harness.

STEP 3C-1: Check for an open circuit in

the engine harness.

STEP 3D: Check for a pin to pin short

circuit in the engine harness.

STEP 3E: Check for an inactive fault code. Fault Code 1678 inactive?

Dirty or damaged pins?

Fault Code 1678 is inactive?

Less than 10 ohms?

Less than 10 ohms?

Greater than 100K ohms?

STEP 4: Clear the fault code.

STEP 4A: Disable the fault code. Fault Code 1678 inactive?

STEP 4B: Clear the inactive fault codes. All fault codes cleared?

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ISB, ISBe2, ISBe3, ISBe4, QSB4 [...]
Section TF - Troubleshooting Fault Codes Page TF-57

TROUBLESHOOTING STEP

STEP 1: Check the fault codes.

STEP 1A: Check for an inactive fault code.

Condition:

• Turn keyswitch ON.

• Connect INSITE™ electronic service tool.

Action Specification/Repair Next Step

Check for an inactive fault code.

• Use INSITE™ electronic service tool to read
the fault codes.

Fault Code 1678 inactive?

YES

Fault Code 1678 inactive?

NO

STEP 2: Check the catalyst solution temperature sensor and circuit.

STEP 2A: Inspect the catalyst solution temperature sensor and connector pins.

Condition:

• Turn keyswitch OFF.

• Disconnect the catalyst solution temperature sensor from the engine harness.

Action Specification/Repair Next Step

Inspect the engine harness and catalyst sensor
temperature sensor connector pins for the
following:

• Loose connector

• Corroded pins

• Bent or broken pins

• Pushed back or expanded pins

• Moisture in or on the connector

• Missing or damaged connector seals

• Dirt or debris in or on the connector pins

• Connector shell broken

• Wire insulation damage

• Damaged connector locking tab.

Use the following procedure for general
inspection techniques. Refer to Procedure
019-361 in Section 19.

Dirty or damaged pins?

YES

Repair:

A damaged connection has been detected in
the sensor or harness connector.

Clean the connector and pins.

Repair the damaged harness, connector, or
pins if possible. Refer to Procedure 019-071
in Section 19.

Dirty or damaged pins?

NO

Use the
following
procedure for
an inactive or
intermittent
fault code.
Refer to
Procedure
019-362 in
Section 19.

2A

4A

2B

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Page TF-58 Section TF - Troubleshooting Fault Codes

STEP 2B: Check the sensor resistance.

Condition:

• Turn keyswitch OFF.

• Disconnect the catalyst solution temperature sensor from the engine harness.

Action Specification/Repair Next Step

Measure the sensor resistance.

• Measure the resistance between the catalyst
solution temperature sensor SIGNAL pin and
catalyst solution temperature sensor RETURN
pin at the catalyst solution temperature
sensor.

Refer to the wiring diagram for connector pin
identification.

Use the following procedure for general
resistance measurement techniques. Refer to
Procedure 019-360 in Section 19.

180 ohms to 160k ohms?

YES

180 ohms to 160k ohms?

NO

Repair:

Replace the catalyst solution temperature
sensor. Refer to the OEM service manual.

2C

4A

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Section TF - Troubleshooting Fault Codes Page TF-59

STEP 2C: Check the fault codes and verify sensor condition.

Condition:

• Turn keyswitch OFF.

• Connect the catalyst solution temperature sensor to the engine harness.

• Turn keyswitch ON.

• Connect INSITE™ electronic service tool.

Action Specification/Repair Next Step

Check for the appropriate circuit response after
30 seconds.

• Use INSITE™ electronic service tool to read

Fault Code 1678 is active?

YES

the fault codes.

Fault Code 1678 is active?

NO

Repair:

None. The removal and installation of the
connector corrected the fault.

STEP 3: Check the ECM and engine harness.

STEP 3A: Inspect the ECM and engine harness connector pins.

Condition:

• Turn keyswitch OFF.

• Disconnect the engine harness from the ECM connector.

Action Specification/Repair Next Step

:Inspect the engine harness and ECM connector
pins for the following:

• Loose connector

• Corroded pins

• Bent or broken pins

• Pushed back or expanded pins

• Moisture in or on the connector

• Missing or damaged connector seals

• Dirt or debris in or on the connector pins

• Connector shell broken

• Wire insulation damage

• Damaged connector locking tab.

Use the following procedure for general
inspection techniques. Refer to Procedure
019-361 in Section 19.

Dirty or damaged pins?

YES

Repair:

A damaged connection has been detected in
the ECM connector or the engine harness
connector.

Clean the connector and pins.

Repair the damaged harness, connector, or
pins if possible. Refer to Procedure 019-043
in Section 19.

Dirty or damaged pins?

NO

3A

4A

4A

3B

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Page TF-60 Section TF - Troubleshooting Fault Codes

STEP 3B: Check the circuit response.

Condition:

• Turn keyswitch OFF.

• Disconnect the engine harness from the ECM.

• Turn keyswitch ON.

• Connect INSITE™ electronic service tool.

Action Specification/Repair Next Step

Place a jumper wire between the catalyst
solution temperature sensor SIGNAL pin and the
catalyst solution temperature sensor RETURN
pin at the ECM connector.

• Check for the appropriate circuit response
after 30 seconds.

• Use INSITE™ electronic service tool to read
the fault codes.

Refer to the wiring diagram for connector pin
identification.

Fault Code 1677 active and Fault Code 1678
is inactive?

YES

Fault Code 1677 active and Fault Code 1678
is inactive?

NO

Repair:

Replace the ECM. Refer to Procedure
019-031 in Section 19.

3C

4A

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Section TF - Troubleshooting Fault Codes Page TF-61

STEP 3C: Check for an open circuit in the engine harness.

Condition:

• Turn keyswitch OFF.

• Disconnect the engine harness from the ECM.

• Disconnect the catalyst solution temperature sensor from the engine harness.

Action Specification/Repair Next Step

Check for an open circuit.

• Measure the resistance between the engine
harness ECM connector catalyst solution
temperature sensor RETURN pin and the
engine harness catalyst solution temperature
sensor connector RETURN pin.

Refer to the wiring diagram for connector pin
identification.

Use the following procedure for general
resistance measurement techniques. Refer to
Procedure 019-360 in Section 19.

Less than 10 ohms?

YES

Less than 10 ohms?

NO

Repair:

An open RETURN circuit has been detected
in the engine harness.

Repair or replace the engine harness. Refer
to Procedure 019-043 in Section 19.

3C-1

4A

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Page TF-62 Section TF - Troubleshooting Fault Codes

STEP 3C-1: Check for an open circuit in the engine harness.

Condition:

• Turn keyswitch OFF.

• Disconnect the engine harness from the ECM.

• Disconnect the catalyst solution temperature sensor from the engine harness.

Action Specification/Repair Next Step

Check for an open circuit.

• Measure the resistance between the engine
harness ECM connector catalyst solution
temperature sensor SIGNAL pin and the
engine harness catalyst solution temperature
sensor connector SIGNAL pin.

Refer to the wiring diagram for connector pin
identification.

Use the following procedure for general
resistance measurement techniques. Refer to
Procedure 019-360 in Section 19.

Less than 10 ohms?

YES

Less than 10 ohms?

NO

Repair:

An open SIGNAL circuit has been detected
in the engine harness.

Repair or replace the engine harness. Refer
to Procedure 019-043 in Section 19.

3D

4A

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Section TF - Troubleshooting Fault Codes Page TF-63

STEP 3D: Check for a pin-to-pin short circuit in the engine harness.

Condition:

• Turn keyswitch OFF.

• Disconnect the engine harness from the ECM.

• Disconnect the catalyst solution temperature sensor from the engine harness.

Action Specification/Repair Next Step

Check for a pin-to-pin short.

• Measure the resistance between the catalyst
solution temperature sensor SIGNAL pin in the
engine harness ECM connector and all other
pins in the engine harness ECM connector.

Refer to the wiring diagram for connector pin
identification.

Use the following procedure for general
resistance measurement techniques. Refer to
Procedure 019-360 in Section 19.

Greater than 100K ohms?

YES

Greater than 100K ohms?

NO

Repair:

A pin-to-pin short circuit on the SIGNAL line
has been detected in the engine harness.

Repair or replace the engine harness. Refer
to Procedure 019-043 in Section 19.

3E

4A

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Page TF-64 Section TF - Troubleshooting Fault Codes

STEP 3E: Check for an inactive fault code.

Condition:

• Connect all components.

• Turn keyswitch ON.

• Connect INSITE™ electronic service tool.

Action Specification/Repair Next Step

Check for the appropriate circuit response after
30 seconds.

• Use INSITE™ electronic service tool to read
the fault codes.

STEP 4: Clear the fault code.

STEP 4A: Disable the fault code.

Condition:

• Connect all components.

• Turn keyswitch ON.

• Connect INSITE™ electronic service tool.

Action Specification/Repair Next Step

Fault Code 1678 inactive?

YES

Repair:

None. The removal and installation of the
connector corrected the fault.

Fault Code 1678 inactive?

NO

Repair:

Troubleshooting procedures need to be
repeated from the beginning. A failure mode
should have been detected.

4A

1A

Disable the fault code.

• Start the engine and let it idle for 1 minute.

• Use INSITE™ electronic service tool to verify
the fault code is inactive.

STEP 4B: Clear the inactive fault codes.

Condition:

• Connect all components.

• Turn keyswitch ON.

• Connect INSITE™ electronic service tool.

Action Specification/Repair Next Step

Clear the inactive fault codes.

• Use INSITE™ electronic service tool to erase
the inactive fault codes.

Fault Code 1678 inactive?

YES

Fault Code 1678 inactive?

NO

All fault codes cleared?

YES

All fault codes cleared?

NO

4B

1A

Repair
complete

Appropriate
troubleshooti
ng steps

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ISB, ISBe2, ISBe3, ISBe4, QSB4 [...] Catalyst Tank Temperature — Data Erratic, Intermittent, [...]
Section TF - Troubleshooting Fault Codes Page TF-65

Fault Code 1679

Catalyst Tank Temperature — Data Erratic, Intermittent, or Incorrect

CODES REASON EFFECT

Fault Code: 1679
PID(P), SID(S):
SPN: 3031
FMI: 2
Lamp: Amber
SRT:

Catalyst Tank Temperature —
Data Erratic, Intermittent, or
Incorrect. The catalyst solution
temperature sensor is not
changing with engine operating
conditions.

Default temperature value used for catalyst
solution temperature.

Circuit: Catalyst Solution Temperature Sensor

Circuit Description:

The catalyst solution temperature sensor is used by the electronic control module (ECM) to monitor the temperature of
the catalyst solution in the catalyst tank. The ECM monitors the voltage on the signal pin and converts this to a
temperature value.

Component Location:

The catalyst solution temperature sensor is located in the catalyst tank. The tank is OEM mounted. For more
information, contact the OEM service manual.

Shop Talk:

This diagnostic runs when the engine has not been running for at least eight hours. The catalyst solution temperature
sensor is compared to engine coolant temperature and intake manifold temperature when the key is turned on after
the extended eight hour shutdown. This fault code is logged if the reading from the catalyst solution temperature
sensor does not match the readings from engine coolant temperature and intake manifold temperature.

Possible causes of this fault code include:

• Stuck in-range catalyst solution temperature sensor

• High resistance in the catalyst solution temperature sensor signal or return lines.

On-Board Diagnostics (OBD) Information (Euro 4 and Euro 4 Stage 1+ Certified Engines):

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Page TF-66 Section TF - Troubleshooting Fault Codes

• The ECM illuminates the malfunction indicator lamp (MIL) on the second consecutive ignition cycle that the
diagnostic runs and fails.

• The ECM turns OFF the malfunction indicator lamp (MIL) after 3 consecutive ignition cycles that the diagnostic runs
and does not fail. The MIL lamp and fault code can also be cleared using the INSITE™ service tool.

• The fault code will be cleared from memory after 40 consecutive drive cycles where the diagnostic runs and passes.

Refer to Troubleshooting Fault Code t05-1679

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Section TF - Troubleshooting Fault Codes Page TF-67

TROUBLESHOOTING SUMMARY

CAUTION
To reduce the possibility of damaging a new ECM, all other active fault codes must be investigated prior to
replacing the ECM.

CAUTION
To reduce the possibility of pin and harness damage, use the following test leads when taking a
measurement:Part Number 3822758 - male Deutsch/AMP/Metri-Pack test leadPart Number 3822917 - female
Deutsch/AMP/Metri-Pack test lead.

STEPS SPECIFICATIONS SRT CODE
STEP 1: Check for sensor circuit fault codes.

STEP 1A: Check for fault codes. Fault Code 1677 or 1678 is

active?

STEP 2: Check the catalyst solution temperature sensor and circuit.

STEP 2A: Inspect the catalyst solution

temperature sensor and
connector pins.

STEP 2B: Check the circuit response. Fault Code 1678 active?

STEP 2C: Check the circuit response. Fault Code 1677 active?

Dirty or damaged pins?

STEP 3: Check the ECM and engine harness.

STEP 3A: Inspect the ECM and engine

harness connector pins.

STEP 3B: Check the circuit response. Fault Code 1678 active?

STEP 3C: Check the circuit response. Fault Code 1677 active?

Dirty or damaged pins?

STEP 4: Clear the fault codes.

STEP 4A: Verify the repair Catalyst Solution Temperature

and the Thermometer are
reading within 5°F of each
other?

STEP 4B: Clear the fault codes. All fault codes cleared?

TROUBLESHOOTING STEP

STEP 1: Check for sensor circuit fault codes.

STEP 1A: Check for fault codes.

Condition:

• Turn keyswitch ON.

• Connect INSITE™ electronic service tool.

Action Specification/Repair Next Step

Check for an active fault codes.

• Use INSITE™ to read the fault codes.

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Fault Codes 1677 or 1678 is active?

YES

Fault Code 1677 or 1678 is active?

NO

Appropriate
fault code
troubleshooti
ng tree.

2A

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Page TF-68 Section TF - Troubleshooting Fault Codes

STEP 2: Check the catalyst solution temperature sensor and circuit.

STEP 2A: Inspect the catalyst solution temperature sensor and connector pins.

Condition:

• Turn keyswitch OFF.

• Disconnect the catalyst solution temperature sensor from the engine harness.

Action Specification/Repair Next Step

Inspect the engine harness and catalyst solution
temperature sensor connector pins for the
following:

• Corroded pins

• Bent or broken pins

• Pushed back or expanded pins

Dirty or damaged pins?

YES

Repair:

A defective connection has been detected in
the sensor or harness connector.

• Wire insulation damage

• Moisture in or on the connector

• Missing or damaged connector seals

• Connector shell broken

• Dirt or debris in or on the connector pins

Clean the connector and pins.

Repair the damaged harness, connector, or
pins if possible.

Refer to Procedure 019-071.

For general inspection techniques, refer to
Component Connector and Pin Inspection, Refer
to Procedure 019-361.

Dirty or damaged pins?

NO

STEP 2B: Check the circuit response.

Condition:

• Turn keyswitch OFF.

• Disconnect the catalyst solution temperature sensor from the engine harness.

• Turn keyswitch ON.

• Connect INSITE™ electronic service tool.

Action Specification/Repair Next Step

4A

2B

Check for the appropriate ECM response after
30 seconds.

• Use INSITE™ to read the fault codes.

Fault code 1678 active?

YES

Fault code 1678 active?

NO

2C

3A

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Section TF - Troubleshooting Fault Codes Page TF-69

STEP 2C: Check the circuit response.

Condition:

• Turn keyswitch OFF.

• Disconnect the catalyst solution temperature sensor from the engine harness.

• Turn keyswitch ON.

• Connect INSITE™ electronic service tool.

Action Specification/Repair Next Step

Place a jumper wire between the catalyst
solution temperature SIGNAL pin and the
catalyst solution temperature RETURN pin at the
catalyst solution temperature connector of the
engine harness.

Refer to the wiring diagram for connector pin
identification.

Check the appropriate circuit response after 30
seconds.

• Use INSITE™ to read the fault codes.

Fault Code 1677 is active?

YES

Repair:

Replace the catalyst solution temperature
sensor.

Refer to OEM troubleshooting procedures.

Fault Code 1677 is active?

NO

4A

3A

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