Bendix Commercial Vehicle Systems EC-80 User Manual

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Bendix® EC-80™ ABS / ATC Controllers

Two Connectors

Are Used

SD-13-4983

Bendix® EC‑80™ ATC ControllerBendix® EC‑80™ ABS Controller

Three Connectors

Are Used

See SD‑13‑21021 for the Bendix® eTrac™ Automated Air Suspension Transfer System

Bendix® EC‑80™ ESP(+) Controllers will be featured in SD‑13‑4986.

INTRODUCTION

Bendix® EC‑80™ ABS and ATC controllers are members of a family of electronic Antilock Braking System (ABS) devices designed to help improve the braking characteristics of air braked vehicles ‑ including heavy‑ and medium‑duty buses, trucks, and tractors. ABS controllers are also known as Electronic Control Units (ECUs).

Bendix® ABS uses wheel speed sensors, ABS modulator valves, and an ECU to control either four or six wheels of a vehicle. By monitoring individual wheel turning motion during braking, and adjusting or pulsing the brake pressure at each wheel, the Bendix EC‑80 controller is able to optimize slip between the tire and the road surface. When excessive wheel slip, or wheel lock‑up is detected, the Bendix EC‑80 controller will activate the Pressure Modulator Valves to simulate a driver pumping the brakes. However, the Bendix EC‑80 controller is able to pump the brakes on individual wheels (or pairs of wheels) independently, and with greater speed and accuracy than a driver.

In addition to the ABS function, the ATC version of the Bendix EC‑80 controller provides an Automatic Traction Control (ATC) feature. Bendix® ATC can improve vehicle traction during acceleration, plus lateral stability while driving through curves. ATC utilizes Engine Torque Limiting (ETL) where the ECU communicates with the engine’s controller and/or Differential Braking (DB) where individual wheel brake applications are used to improve vehicle traction.

Bendix EC‑80 ATC controllers also have the capability to provide a Hill Start Assist (HSA) feature. HSA interfaces

FIGURE 1 - BENDIX® EC‑80™ ABS AND ATC CONTROLLERS

The driver is always responsible for the control and safe operation of the vehicle at all times. The Bendix® ABS system does not replace the need for a skilled, alert professional driver, reacting appropriately and in a timely manner, and using safe driving practices.

TABLE OF CONTENTS PAGE

Introduction...................................1‑2

Component/ECU Mounting.......................2‑3

ABS Off‑Road Switch and Indicator Lamp Operation.....4

Bendix EC‑80 Controller Outputs ....................4

Indicator Lamp Behavior.........................5‑6

Power‑Up Sequence ...........................6‑7

ABS Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7

ATC Operation ................................8‑9

Dynamometer Test Mode .......................9‑10

Automatic Tire Size Calibration ....................10

ABS Partial Shutdown ...........................10

System Reconguration .........................11

Blink Codes ...................................13

Diagnostic Modes...............................14

Using hand‑held or PC‑based diagnostics ............16

Diagnostic Trouble Code Index ....................18

Troubleshooting: Wiring .......................32‑37

Glossary ......................................39

Appendix: J1939 SPN and FMI Codes............40‑43

GENERAL SAFETY GUIDELINES

WARNING! PLEASE READ AND

FOLLOW THESE INSTRUCTIONS

TO AVOID PERSONAL INJURY OR DEATH:

When working on or around a vehicle, the following guidelines should be observed AT ALL TIMES:

▲ Park the vehicle on a level surface, apply the parking

brakes and always block the wheels. Always wear personal protection equipment.

▲ Stop the engine and remove the ignition key when

working under or around the vehicle. When working in the engine compartment, the engine should be shut off and the ignition key should be removed. Where circumstances require that the engine be in operation, EXTREME CAUTION should be used to prevent personal injury resulting from contact with moving, rotating, leaking, heated or electrically-charged components.

▲ Do not attempt to install, remove, disassemble or

assemble a component until you have read, and thoroughly understand, the recommended procedures. Use only the proper tools and observe all precautions pertaining to use of those tools.

▲ If the work is being performed on the vehicle’s air brake

system, or any auxiliary pressurized air systems, make certain to drain the air pressure from all reservoirs before beginning ANY work on the vehicle. If the vehicle is equipped with a Bendix Bendix

DRM™ dryer reservoir module, or a Bendix

AD-9si™ air dryer, be sure to drain the purge reservoir.

▲

Following the vehicle manufacturer’s recommended procedures, deactivate the electrical system in a manner

that safely removes all electrical power from the vehicle ▲ Never exceed manufacturer’s recommended pressures. ▲ Never connect or disconnect a hose or line containing

pressure; it may whip. Never remove a component or

plug unless you are certain all system pressure has

been depleted. ▲ Use only genuine Bendix

components and kits. Replacement hardware, tubing,

hose,  ttings, etc. must be of equivalent size, type

and strength as original equipment and be designed

speci cally for such applications and systems.

▲ Components with stripped threads or damaged parts

should be replaced rather than repaired. Do not

attempt repairs requiring machining or welding unless

speci cally stated and approved by the vehicle and

component manufacturer. ▲ Prior to returning the vehicle to service, make certain all

components and systems are restored to their proper

operating condition. ▲ For vehicles with Automatic Traction Control (ATC),

the ATC function must be disabled (ATC indicator

lamp should be ON) prior to performing any vehicle

maintenance where one or more wheels on a drive axle

are lifted off the ground and moving. ▲ The power MUST be temporarily disconnected

from the radar sensor whenever any tests USING A

DYNAMOMETER are conducted on a Bendix

Advanced

™

-equipped vehicle.

▲ You should consult the vehicle manufacturer's

operating and service manuals, and any related

literature, in conjunction with the Guidelines above.

AD-IS® air dryer system, a

brand replacement parts,

Wingman®

between the transmission and braking system to help the driver prevent the vehicle from rolling backwards when moving forward from a stationary position on steep inclines.

Bendix® EC‑80™ ATC controllers have a drag torque control feature which reduces driven‑axle wheel slip (due to driveline inertia) by communicating with the engine’s controller and increasing the engine torque.

COMPONENTS/ECU MOUNTING

The Bendix EC‑80 controller’s ABS function uses:

• Bendix® WS‑24™ wheel speed sensors (4 or 6,

depending on ECU and conguration). Each sensor is

installed with a Bendix® Sensor Clamping Sleeve

• Bendix® M‑32™ / M‑32QR™ / M‑40X™ Pressure Modulator Valves (4, 5, or 6 depending on ECU and

conguration)

• Dash‑mounted tractor ABS indicator lamp

• Service brake relay valve

• Dash‑mounted trailer ABS indicator lamp (used on all towing vehicles manufactured after March 1, 2001)

• Optional blink code activation switch

• Optional ABS off‑road switch. (Off‑road feature is not available on all ECUs ‑ See Chart 1.)

90° Speed

Sensors

FIGURE 2 - BENDIX® WS‑24™ WHEEL SPEED SENSORS

M-32QR

Modulator

™

Delivery

(Port 2)

Supply (Port 1)

Electrical

Connector

Exhaust (Port 3)

™

M-40X

Modulators

FIGURE 3 - BENDIX® M‑32™ AND M‑40X™ MODULATORS

Sensor

Clamping

Sleeve

Straight Speed

Sensors

™

M-32

Modulator

The Automatic Traction Control (ATC) function uses the following additional components:

• Traction control valve (may be integral to the service brake relay valve or a stand‑alone device)

• Dash‑mounted ATC status/indicator lamp

• J1939 serial communication to engine control module

• Stop lamp switch input (may be provided using the ECU hardware input or J1939)

• Optional ATC off‑road switch

The Hill Start (HSA) function uses the following components:

• Traction Control Valve (TCV)

• Dash‑mounted HSA status/indicator lamp

• Dash‑mounted Enable/Disable switch

• RV‑3 Pressure Reducing Valve

• DC‑4 Double Check valve

ECU MOUNTING

Bendix® EC‑80™ controllers are cab‑mounted. They are not protected against moisture and must be mounted in an environmentally protected location.

All wire harness connectors must be properly seated. The use of secondary locks is strongly recommended.

Bendix EC-80 ATC Controllers

Bendix EC‑80 ATC controllers support applications up to six sensor/six modulator (6S/6M) installations with ATC and drag torque control. They can support HSA functions. All 12 volt models support Power Line Carrier (PLC). 24 volt models do not support PLC. See Chart 1 for more details.

BENDIX EC-80 CONTROLLERS WITH PLC

Since March 1, 2001, all towing vehicles must have an in‑cab trailer ABS indicator lamp. Trailers transmit the status of the trailer ABS over the power line (the blue wire of the J560 connector) to the tractor using a PLC signal. See Figures 4 and 5.

FIGURE 4 - POWER LINE WITHOUT PLC SIGNAL

All unused ECU connectors must be covered and receive any necessary protection from moisture, etc.

ECUs utilize connectors from the AMP MCP 2.8 product family.

HARDWARE CONFIGURATIONS

Bendix® EC-80™ ABS Controllers

Bendix EC‑80 ABS controllers support four sensor/four modulator (4S/4M) applications. Certain models support Power Line Carrier (PLC) communications, with all models supporting 12 volt installations. See Chart 1 for more

details.

ECU Mounting

Bendix EC-80 ABS

controller

Bendix EC-80 ABS

PLC controller

Bendix EC-80 ATC

controller

Bendix EC-80 ATC

controller

Cab 12 4 4 - - - -

Cab 12 4 4 - - -

Cab 12 4/6 4/5/6

Cab 24 4/6 4/5/6 -

Input

Voltage

Sensors PMVs ATC

FIGURE 5 - POWER LINE WITH PLC SIGNAL

Typically the signal is broadcast by the trailer ABS ECU. The application of PLC technology for the heavy vehicle industry is known as “PLC4Trucks.” The Bendix EC‑80

Serial

Blink

Codes

CHART 1 - BENDIX® EC‑80™ CONTROLLERS AVAILABLE

Commu‑

nication

J1939

PLC

ABS

Off-

Road

ATC

Off-

Road

Retarder

Relay

PLC controller and the Bendix EC‑80 ATC controller (12 volt versions) support PLC communications in accordance with SAE J2497.

Identifying a Bendix EC-80 Controller with PLC

Refer to the information panel on the ECU label to see if the controller provides PLC.

An oscilloscope can be used to measure or identify the presence of a PLC signal on the power line. The PLC signal is an amplitude and frequency‑modulated signal.

Depending on the ltering and load on the power line,

the PLC signal amplitude can range from 5.0 mVp‑p to 7.0 Vp‑p. Suggested oscilloscope settings are AC coupling, 1 volt/div, 100 µsec/div. The signal should be measured at the ignition power input of the Bendix EC‑80 controller.

Note: An ABS trailer equipped with PLC or a PLC diagnostic tool must be connected to the vehicle in order to generate a PLC signal on the power line.

To conrm if a specic ECU uses PLC or not, see the Controller Specications box below.

BENDIX EC-80 CONTROLLER INPUTS

Battery and Ignition Inputs

The ECU operates at a nominal supply voltage of 12 or 24 volts, depending on the ECU. The battery input is connected through a 30 amp fuse directly to the battery.

The ignition input is applied by the ignition switch through a 5 amp fuse.

Vehicle axle congurations and ATC features determine

the number of Bendix WS‑24™ wheel speed sensors that must be used. A vehicle with a single rear axle requires four wheel speed sensors. Vehicles with two rear axles can utilize six wheel speed sensors for optimal ABS and ATC performance.

Diagnostic Blink Code Switch

A momentary switch that grounds the ABS indicator lamp output is used to place the ECU into the diagnostic blink code mode and is typically located on the vehicle’s dash panel.

ABS OFF-ROAD SWITCH AND INDICATOR LAMP OPERATION

The ABS off-road mode should not be used on normal, paved road surfaces because vehicle stability and steerability may be affected. When the ECU is placed in the ABS off-road mode, the ABS indicator lamp will

ash constantly to notify the vehicle operator that the

off-road mode is active.

Bendix EC‑80 ATC controllers use a dash‑mounted switch to place the ECU into the ABS off‑road mode. In some cases, ECUs may also be put into the ABS off‑road mode by one of the other vehicle control modules, using a J1939 message to the Bendix EC‑80 controller.

If you need to know if a specic ECU uses a J1939 message to operate the lamp, see the Controller Specications box below.

Ground Input

The Bendix EC‑80 controller supports one ground input.

See pages 35-37 for electrical system schematics.

ABS Indicator Lamp Ground Input

Bendix EC‑80 ECUs require a second ground input (X1‑12) for the ABS indicator lamp. The X1 wire harness connector contains an ABS indicator lamp interlock (X1‑15), which shorts the ABS indicator lamp circuit (X1‑18) to ground if the connector is removed from the ECU.

Bendix® WS-24™ Wheel Speed Sensors

Wheel speed data is provided to the Bendix EC‑80 controller from the Bendix® WS‑24™ wheel speed sensor (see Figure

2). Vehicles have an exciter ring (or “tone ring”) as part of the wheel assembly, and as the wheel turns, the teeth of the exciter ring pass the wheel speed sensor, generating an AC signal. The Bendix EC‑80 controller receives the AC signal, which varies in voltage and frequency as the wheel speed changes.

Controller Specications: If you need to know exact information about an ECU e.g. if it uses PLC, serial communications, etc., e-mail ABS@Bendix.com, specifying the ECU part number, or call:

1-800-AIR-BRAKE, 1-800-247-2725, option 2, then 1, and speak to the Bendix TechTeam.

Stop Lamp Switch (SLS)

Bendix EC‑80 ATC ECUs monitor the vehicle stop lamp status. Certain vehicle functions, such as ATC and All‑ Wheel Drive (AWD), use the status of the stop lamp to know the driver’s intention. This can be provided to the ECU via J1939 communications or hardware input.

BENDIX EC-80 CONTROLLER OUTPUTS

Bendix® M-32™, M-32QR™ and M-40X™ Pressure Modulator Valves (PMV)

The Bendix M‑32, M‑32QR and M‑40X pressure modulator valves (PMV) are operated by the Bendix EC‑80 controller to modify driver applied air pressure to the service brakes during ABS or ATC activation (See pages 6‑8). The PMV is an electro‑pneumatic control valve and is the last valve that air passes through on its way to the brake chamber. The modulator hold and release solenoids are activated to precisely modify the brake pressure during an antilock braking event. The hold solenoid is normally open and the release solenoid is normally closed.

Dash Lamps

ATC

ABS

TRLR

HSA

Mode

Ignition on ‑ start up

(trailer with PLC)

3 seconds after ignition

At Vehicle Startup

(with no Diagnostic

Trouble Codes)

ABS

Off-Road

Mode

Deep

Special Mode Operation

Mud/

Snow/

Mode

Normal

During an ATC

Event

Vehicles with Hill Start Feature: During HSA Mode Lamp OFF

Normal OFF

During an ATC

Event

ABS

Lamp

ON for 3 sec‑

onds*

Lamp OFF* Lamp OFF* Lamp OFF**

Lamp ashes

slowly (every 2.5

seconds)

‑— OR, depending on vehicle options (a vehicle can have either ABS off‑road or HSA) —

OFF Flashes quickly

ATC

Lamp

ON for 2.5

seconds*

Lamp OFF

Flashes quickly

Flashes slowly

(every 2.5

seconds)

Trailer

ABS Lamp

ON for 3

seconds**

• Uses dash switch

• Not for rm road surfaces

• Allows more wheel lock‑up (less ABS intervention)

• Mode only applies under 25 mph (Over 25 mph, the system reverts to full ABS ‑ including ATC, and ATC lamp goes off.)

• Uses dash switch

• Increases allowable wheel slip during ATC interventions

• Not for rm road surfaces

HSA

Lamp

ON for 3

seconds*

Lamp

OFF*

Comments

If any of the described lamp behaviors do

not occur — or if the lamp remains on during operation — have the vehicle serviced by a

qualied mechanic as soon as possible to

restore full system functionality.

Some vehicle manufacturers may illuminate

the trailer ABS indicator lamp at power‑up regardless of whether a PLC signal is detected from the trailer or not. Consult the vehicle manufacturer’s documentation for more details.

• The HSA lamp is illuminated only at power‑ up, or if an HSA DTC is present

• If the driver disables HSA, the HSA lamp will

ash slowly

During an Automatic Traction Control (ATC) Event Flashes quickly • Reduces wheel slip during acceleration at low speeds

During Dynamometer Mode

ABS System

Status Indicators

at Start-Up

Powered Vehicle ABS

Indicator Lamp

Trailer ABS

Indicator Lamp

(PLC Detected)**

Trailer ABS Indicator

Lamp**

(PLC Not Detected)

OFF

0.5 2.0 2.5 3.0 (sec.)1.5

Lamp ON

(ATC

Disabled)

Power

Application

• Disables ATC monitoring functions

• When not in Dynamometer Mode, an illuminated lamp indicates an ATC DTC is present

ATC System

Status Indicator

at Start-Up

ATC

enabled

No ATC

0.5 2.0 2.5 3.0 (sec.)1.5

OFF

Power

Application

CHART 2 - BENDIX® EC‑80™ INDICATOR LAMP BEHAVIOR

Traction Control Valve (TCV)

Bendix EC‑80 ATC controllers will activate the TCV during differential braking ATC events. The TCV may be a separate valve or integrated into the rear axle relay valve.

ABS Indicator Lamp Control with Optional Diagnostic Blink Code Switch

Bendix® EC‑80™ controllers have internal circuitry to control the ABS indicator lamp on the dash panel.

The ABS Lamp Illuminates:

1. During power‑up (e.g. when the vehicle is started) and turns off after the self‑test is completed, providing no Diagnostic Trouble Codes (DTCs) are present on the tractor.

2. If the ECU is unplugged or has no power.

3. When the ECU is placed into the ABS off‑road mode

(the lamp ashes rapidly).

4. To display blink codes for diagnostic purposes after the external diagnostic switch is activated.

Certain Bendix® EC‑80™ controllers communicate with other vehicle control modules to operate the ABS indicator lamp using. To conrm if a specic ECU uses serial communications, see the Controller Specications box

on page 4.

Indicator Lamp Control Using Serial Communications Links

As mentioned above, depending on the vehicle manufacturer, the dash indicator lamps (ABS, ATC and trailer ABS) may be controlled using serial communications link. In these cases, the Bendix EC‑80 controller will send a serial communications message over the J1939 links indicating the required status of the lamp(s). Another vehicle control module receives the message and controls the indicator lamp(s).

Retarder Relay Disable Output

The retarder relay disable output may be used to control a retarder disable relay.

When congured to use this output, the ECU will energize

the retarder disable relay and inhibit the use of the retarder as needed.

SAE J1939 Serial Communications

A Controller Area Network (CAN) data link (SAE J1939) is provided for communication. This link is used for various functions, such as:

• To disable retarding devices during ABS operation

• To request that the torque converter disable lock‑up

during ABS operation

• To share information such as wheel speed and ECU

status with other vehicle control modules

Bendix EC‑80 ATC controllers utilize the J1939 data link for ATC and drag torque control functions.

Trailer ABS Indicator Lamp Control

Certain models of the Bendix EC‑80 controller activate a trailer ABS indicator lamp (located on the dash panel) that indicates the status of the trailer ABS unit on one, or more trailers or dollies. Typically, the Bendix EC‑80 controller directly controls the trailer ABS indicator lamp based on the information it receives from the trailer ABS.

Alternatively, some vehicles require the Bendix EC‑80 controller to activate the trailer ABS indicator lamp by communicating with other vehicle controllers using serial communications. To conrm if a specic ECU uses serial communications, see the Controller Specications box on

page 4.

ATC Lamp Output/ATC Off-Road Switch Input

The ATC dash lamp is controlled by the Bendix EC‑80 ATC ECU. The ATC lamp illuminates:

1. During power‑up (e.g. when the vehicle is started for approximately 2.5 seconds) and turns off after the self‑test is completed, providing no Diagnostic Trouble Codes are present.

2. When ATC is disabled for any reason.

3. During an ATC event (the lamp will ash rapidly at a

rate of 2.5/second).

4. When the ECU is placed in the ATC off‑road mode (the

lamp will ash steadily every 2.5 seconds). This noties

the vehicle operator that the off‑road mode is active.

Interaxle Differential Lock Control (AWD Transfer Case)

A Bendix EC‑80 ATC ECU can control the interaxle differential lock (AWD transfer case). This is recommended

on AWD vehicles, but the ECU must be specially congured

to provide this feature. For help with conguring an ECU, use the information in the Controller Specications box on page 4 to contact Bendix.

POWER-UP SEQUENCE

The vehicle operator should verify proper operation of all installed indicator lamps (ABS, ATC, and trailer ABS) when applying ignition power and during vehicle operation. See Chart 2 on page 5.

Lamps that do not illuminate as expected when ignition power is applied, or remain illuminated, indicate the need for maintenance.

ABS Indicator Lamp Operation

The ECU will illuminate the ABS indicator lamp for approximately three seconds when ignition power is applied, after which the lamp will extinguish if no Diagnostic Trouble Codes are detected.

The ECU will illuminate the ABS indicator lamp whenever full ABS operation is not available due to a Diagnostic Trouble Code. In most cases, partial ABS is still available.

ATC Status/Indicator Lamp Operation

The ECU will illuminate the ATC lamp for approximately

2.5 seconds when ignition power is applied, after which

the lamp will extinguish, if no Diagnostic Trouble Codes are detected.

The ECU will illuminate the ATC indicator lamp whenever ATC is disabled due to a Diagnostic Trouble Code.

Trailer ABS Indicator Lamp Operation

Certain models of the ECU will control the Trailer ABS indicator lamp when a PLC signal (SAE J2497) from a trailer ABS ECU is detected.

Pressure Modulator Valve Chuff Test

Bendix® EC‑80™ controllers will perform a Bendix‑patented Pressure Modulator Valve (PMV) Chuff Test. The Chuff Test is an electrical and pneumatic PMV test that can assist maintenance personnel in verifying proper PMV wiring and installation.

With brake pressure applied, a properly installed PMV will perform one sharp audible exhaust of air by activating the hold solenoid twice and the release solenoid once. If the PMV is wired incorrectly, it will produce two exhausts of air, or none at all.

The Bendix EC‑80 controller will perform a PMV chuff test on all installed modulators in the following order:

• Steer Axle Right PMV

• Steer Axle Left PMV

• Drive Axle Right PMV

• Drive Axle Left PMV

• Additional Axle Right PMV

• Additional Axle Left PMV

The pattern will then repeat itself. See Figure 6.

The ECU will not perform the PMV Chuff Test when wheel speed sensors show that the vehicle is in motion.

Right Steer

Right Drive

Right

Additional

ABS OPERATION

Bendix® ABS uses wheel speed sensors, ABS modulator valves, and an ECU to control either four or six wheels of a vehicle. By monitoring individual wheel turning motion during braking, and adjusting or pulsing the brake pressure at each wheel, the Bendix EC‑80 controller is able to optimize slip between the tire and the road surface. When excessive wheel slip, or wheel lock‑up, is detected, the Bendix EC‑80 controller will activate the pressure modulator valves to simulate a driver pumping the brakes. However, the Bendix EC‑80 controller is able to pump the brakes on individual wheels (or pairs of wheels), independently, and with greater speed and accuracy than a driver.

Steer Axle Control

Although both wheels of the steer axle have their own wheel speed sensor and pressure modulator valve, the Bendix EC‑80 controller blends the applied braking force between the two steering axle brakes. This Bendix‑patented brake

application control, called Modied Individual Control (MIC),

is designed to help reduce steering wheel pull during an ABS event on road surfaces with poor traction (or areas of poor traction, e.g., asphalt road surfaces with patches of ice).

Single Drive Axle Control (4x2 Vehicle)

For vehicles with a single rear drive axle (4x2), the brakes are operated independently by the Bendix EC‑80 controller, based on the individual wheel behavior.

Dual Drive Axle Control (4S/4M Conguration)

For vehicles with dual drive axles (6x4) using a 4S/4M

conguration, one ABS modulator controls both right-side

rear wheels, and the other modulator controls both left‑ side rear wheels. Both wheels on each side receive equal brake pressure during an ABS stop. The rear wheel speed sensors must be installed on the axle with the lightest load.

Driver

Left Steer

FIGURE 6 - VEHICLE ORIENTATION (TYPICAL)

Left Drive

Additional

Left

Dual Rear Axle Control (6S/6M Conguration)

For vehicles with dual rear axles (6x4, 6x2) using a 6S/6M

conguration, the rear wheels are controlled independently.

Therefore, brake application pressure at each wheel is adjusted according to the individual wheel behavior on the road surface.

6x2 Vehicles with 6S/5M Conguration

6x2 vehicles can utilize a 6S/5M conguration, with the

additional axle (a non‑driven rear axle) having two sensors, but only one pressure modulator valve. In this case, the PMV controls both wheels on the additional axle. The additional axle wheels would receive equal brake pressure, based on the wheel that is currently experiencing the most wheel slip.

Normal Braking

During normal braking, brake pressure is delivered through the ABS PMV and into the brake chamber. If the ECU does not detect excessive wheel slip, it will not activate ABS control, and the vehicle stops with normal braking.

Retarder Brake System Control

On surfaces with low traction, application of the retarder can lead to high levels of wheel slip at the drive axle wheels, which can adversely affect vehicle stability.

To avoid this, the Bendix EC‑80 controller switches off the retarder as soon as a lock‑up is detected at one (or more) of the drive axle wheels.

When the ECU is placed in the ABS off‑road mode, it will switch off the retarder only when ABS is active on a steer axle wheel and a drive axle wheel.

Optional HSA Mode

As a driver begins to move a vehicle forward when stopped facing up an incline (or backs‑up a vehicle when facing down a slope), vehicles without Bendix Hill Start Aid/Assist (HSA) may experience rolling downhill during the delay between the release of the brakes and providing enough torque to move the vehicle up the slope.

For vehicles with Bendix HSA, the ECU receives a J1939 message from the transmission when it will need the assistance of the brakes to avoid the vehicle rolling. The HSA components apply brake pressure to select wheel‑end brakes. After three (3) seconds from the driver brake release, the HSA system releases the brake pressure. The three‑second delay allows the drive‑line components to activate while the vehicle is held in place.

The ABS off-road mode should not be used on normal, paved road surfaces because vehicle stability and steerability may be reduced. The flashing ABS indicator lamp communicates the status of this mode to the driver.

The vehicle manufacturer should provide the optional ABS off‑road function only for vehicles that operate on unpaved surfaces or that are used in off‑road applications. The vehicle OEM is responsible for ensuring that vehicles equipped with the ABS off‑road function meet all FMVSS‑121 requirements and have adequate operator indicators and instructions.

The vehicle operator activates the off‑road function with a

switch on the dash panel. A ashing ABS indicator lamp

indicates to the driver that the ABS off‑road function is engaged. To exit the ABS off‑road mode, depress and release the switch.

All-Wheel Drive (AWD) Vehicles

AWD vehicles with an engaged interaxle differential (steer axle to rear axle)/AWD transfer case may have negative effects on ABS performance. Optimum ABS performance is achieved when the lockable differentials are disengaged, allowing individual wheel control.

Bendix EC‑80 ATC controllers can be programmed

specically for this conguration to control the differential

lock/unlock solenoid in the AWD transfer case. When programmed to do so, the ECU will disengage the locked interaxle/AWD transfer case during an ABS event and reengage it once the ABS event has ended.

When using the HSA function, the ABS off-road function and the Retarder Relay output are temporarily disabled.

Optional ABS Off-Road Mode

On some road conditions, particularly when the driving surface is soft, the stopping distance with ABS may be longer than without ABS. This can occur when a locked wheel on soft ground plows up the road surface in front of the tire, changing the rolling friction value. Although vehicle stopping distance with a locked wheel may be shorter than corresponding stopping distance with ABS control, vehicle steerability and stability is reduced.

Bendix® EC‑80™ ATC controllers have an optional control mode that more effectively accommodates these soft road conditions to shorten stopping distance while maintaining optimal vehicle steerability and stability.

ATC OPERATION

ATC Functional Overview

Just as ABS improves vehicle stability during braking, ATC improves vehicle stability and traction during vehicle acceleration. The Bendix EC‑80 ATC controller’s ATC function uses the same wheel speed information and modulator control as the ABS function. The ECU detects excessive drive wheel speed; compares the speed of the front, non‑driven wheels; and reacts to help bring the wheel

spin under control. The ECU can be congured to use

engine torque limiting and/or differential braking to control wheel spin. For optimal ATC performance, both methods are recommended.

ATC Lamp Operation

The ATC lamp illuminates:

1. During power‑up (e.g. when the vehicle is started for approximately 2.5 seconds) and turns off after the self‑test is completed, providing no Diagnostic Trouble Codes are present.

2. When ATC is disabled for any reason.

3. During an ATC event (the lamp will ash rapidly at a

rate of 2.5/second). When ATC is no longer active, the ATC active/indicator lamp turns off.

4. When the ECU is placed in the ATC off‑road mode (the

lamp will ash steadily every 2.5 seconds). This noties

the vehicle operator that the off‑road mode is active.

Differential Braking

Differential braking is automatically activated when drive wheel(s) on one side of the vehicle are spinning. This typically occurs on asphalt road surfaces with patches of ice. The traction system will then lightly apply the brake to the drive wheel(s) that are spinning. The vehicle differential will then drive the wheels on the other side of the vehicle.

Differential braking is available at vehicle speeds up to 25 MPH.

Disabling ATC Engine Control and Smart ATC™ Traction Control

ATC Engine Control and Smart ATC™ traction control will be disabled under the following conditions:

1. In response to a serial communications request from an off‑board tool.

2. At power‑up until the ECU detects a service brake application.

3. If the ECU receives a J1939 message indicating that the vehicle is parked.

4. If the Dynamometer Test Mode is active. This may be accomplished via an off‑board tool or the diagnostic blink code switch.

5. When certain Diagnostic Trouble Code conditions are detected.

Disabling ATC Differential Braking

ATC differential braking is disabled under the following conditions:

1. During power‑up (e.g. when the vehicle is started), until the ECU detects a service brake application.

2. If the ECU receives a J1939 message indicating that the vehicle is parked.

3. When the Dynamometer Test Mode is active. The Dynamometer Test Mode is entered using the diagnostic blink code switch or by using a diagnostic tool (such as Bendix® ACom® Diagnostics).

4. In response to a serial communications request from a diagnostic tool.

5. During brake torque limiting to avoid overheating of the brakes.

6. When certain Diagnostic Trouble Code conditions are detected.

Engine Torque Limiting (ETL) with Smart ATC™ Traction Control

The Bendix® EC‑80™ controller uses Engine Torque Limiting to control drive axle wheel slip. This is communicated to the engine control module (using J1939), and is available at all vehicle speeds.

Optional ATC Off-Road Mode

In some road conditions, the vehicle operator may desire additional drive wheel slip when ATC is active. The Bendix EC‑80 ATC controller has an optional control mode to permit this desired performance.

The vehicle operator can activate the off‑road function with a switch on the dash panel. Alternately, a J1939 message may be used to place the vehicle in this mode. The ATC

indicator lamp will ash continually to conrm that the off-

road ATC function is engaged.

To exit the ATC off‑road mode, depress and release the ATC off‑road switch.

Drag Torque Control Functional Overview

Bendix EC‑80 ATC controllers have a feature referred to as drag torque control which reduces wheel slip on a driven axle due to driveline inertia. This condition is addressed by increasing the engine torque to overcome the inertia.

Drag torque control increases vehicle stability on low‑ traction road surfaces during down‑shifting or retarder braking.

DYNAMOMETER TEST MODE

Bendix® Smart ATC™ Traction Control

The Bendix EC‑80 ATC controller has an additional feature known as Smart ATC™ traction control. Smart ATC™ traction control monitors the accelerator pedal position (using J1939) to help provide optimum traction and vehicle stability. By knowing the driver’s intention and adapting the target slip of the drive wheels to the driving situation, the Smart ATC™ traction control allows higher wheel slip when the accelerator pedal is applied above a preset level.

The target wheel slip is decreased when driving through a curve for improved stability.

ATC must be disabled prior to conducting any dynamometer testing. When the Dynamometer Test Mode is enabled, ATC brake control and engine control, along with drag torque control, are turned off. This test mode is used to avoid torque reduction — or torque increase and brake control activation — when the vehicle is operated on a dynamometer for testing purpose.

The Dynamometer Test Mode may be activated by pressing

and releasing the diagnostic blink code switch ve (5) times

or by using a hand‑held or PC‑based diagnostic tool.

The Dynamometer Test Mode will remain active even if power to the ECU is removed and re‑applied. Press and release the blink code switch three (3) times, or use a hand‑held or PC‑based diagnostic tool to exit the test mode.

AUTOMATIC TIRE SIZE CALIBRATION

The ECU requires a precise rolling circumference ratio between steer axle and drive axle tires in order for ABS and ATC to perform in an optimal manner. For this reason, a learning process continuously takes place in which the precise ratio is calculated. This calculated value is stored in the ECU memory provided the following conditions are met:

1. Rolling‑circumference ratio is within the permissible range.

2. Vehicle speed is greater than approximately 15 MPH.

3. No acceleration or deceleration is taking place.

4. There are no active speed sensor Diagnostic Trouble Codes (DTCs).

The ECU is provided with a ratio value of 1.00 as a default setting. If the automatic tire size alignment calculates a

different value, this is used to overwrite the original gure

in the memory. This process adapts the ABS and ATC function to the vehicle.

ABS PARTIAL SHUTDOWN

Depending which component the trouble code is detected on, the ABS and ATC functions may be fully or partially disabled. Even with the ABS indicator lamp on, the Bendix EC‑80™ controller may still provide ABS function on wheels that are not affected. The ECU should be serviced as soon as possible.

Steer Axle ABS Modulator Diagnostic Trouble Code

ABS on the affected wheel is disabled. ABS and ATC on all other wheels remains active.

Drive Axle/Additional Axle ABS Modulator Diagnostic Trouble Code

ATC is disabled. ABS on the affected wheel is disabled. ABS on all other wheels remains active.

Steer Axle Wheel Speed Sensor Diagnostic Trouble Code

The wheel with the Diagnostic Trouble Code is still controlled by using input from the remaining wheel speed sensor on the front axle. ABS remains active on the rear wheels. ATC is disabled.

Acceptable Tire Sizes

The speed calculation for an exciter ring with 100 teeth is based on a default tire size of 510 revolutions per mile.

This gure is based on the actual rolling circumference of

the tires, and varies with tire size, tire wear, tire pressure, vehicle loading, etc.

The ABS response sensitivity is reduced when the actual rolling circumference is excessive on all wheels. For a 100‑tooth exciter ring, the minimum number of tire revolutions per mile is 426, and the maximum is 567. The ECU will set DTCs if the number of revolutions are out of this range.

Drive Axle/Additional Axle Wheel Speed Sensor Diagnostic Trouble Code

ATC is disabled. In a four sensor system, ABS on the affected wheel is disabled, but ABS on all other wheels remains active.

In a six sensor system, ABS remains active by using input from the remaining rear wheel speed sensor on the same side.

ATC Modulator Diagnostic Trouble Code

ATC is disabled. ABS remains active.

J1939 Communication Diagnostic Trouble Code

ATC is disabled. ABS remains active.

ECU Diagnostic Trouble Code

ABS and ATC are disabled. The system reverts to normal braking.

Voltage Diagnostic Trouble Code

While voltage is out of range, ABS and ATC are disabled. The system reverts to normal braking. When the correct voltage level is restored, full ABS and ATC function is available. Operating voltage range is 9.0 to 17.0 VDC.

Reconguring Bendix® EC-80™ Controllers

SYSTEM RECONFIGURATION

The Bendix® EC‑80™ controller is designed to allow the technician to change the default system settings (chosen by the vehicle OEM) to provide additional or customized features. When replacing an ECU, be sure to use an equivalent Bendix® replacement part number so that the standard default settings are provided.

Depending on the version, the customizable features include ABS control settings, engine module communication, etc.

Many of these settings can be recongured using a hand-

held diagnostic tool or PC‑based software, such as the Bendix® ACom® Diagnostics program.

ECU RECONFIGURATION

Reconguring Bendix EC-80 ABS ECUs

Reconguring a Bendix EC‑80 ABS controller may be

carried out by using the Blink Code Switch or by using a hand‑held or PC‑based diagnostic tool.

Note: During the reconguration process, and independently from any reconguration being carried out by the technician,

standard ECUs automatically check the J1939 serial link and communicate with other vehicle modules. In particular, if the serial link shows that the vehicle has a retarder device

present, the ECU will congure itself to communicate with

the retarder device for improved ABS performance. For example, if the ECU detects the presence of a retarder

disable relay during a reconguration, it will congure

itself to control the relay to disable the retarding device as needed.

Reconguring Bendix EC-80 ATC ECUs

As with non‑ATC ECUs, the Bendix EC‑80 ATC ECU also

carries out — independently from any reconguration

being carried out by the technician — an automatic check of the J1939 serial link and communicates with other vehicle modules. This includes checking for ATC and retarder disable relay operation. In addition, Bendix EC‑80 ATC controllers will determine the number of wheel

speed sensors and PMVs installed and congure itself

accordingly.

6S/5M Conguration

Bendix EC-80 ATC controllers will congure for 6S/5M

operation when a reconguration event is initiated and the

ECU detects that an additional axle PMV is wired as follows:

PMV Connector ECU Connector

Hold Right Additional Axle Hold

Release Left Additional Axle Release

Common Right Additional Axle Common

See 6S/5M System Schematic (page 37) for details.

Reconguration Using the Blink Code Switch

The reconguration procedure is the same for ATC and

non‑ATC ECUs. With ignition power removed from the Bendix EC‑80 controller, depress the blink code switch. After the ignition power is activated, depress and release

the switch seven times to initiate a reconguration.

Diagnostic Tool

A reconguration event may be initiated using a hand-held

or PC‑based diagnostic tool to communicate with the ECU over the SAE J1939 diagnostic link.

Troubleshooting: General

Read and follow the General Safety Guidelines on page two (2) of this document.

REMOVING THE BENDIX® EC-80™ CONTROLLER ASSEMBLY

1. Turn vehicle ignition off.

2. Remove as much contamination as possible prior to disconnecting air lines and electrical connections.

3. Note the ECU assembly mounting position on the vehicle.

4. Disconnect the electrical connectors from the ECU.

5. Remove and retain the mounting bolts that secure the ECU.

INSTALLING A NEW BENDIX

EC-80™ CONTROLLER

When replacing the Bendix® EC-80™ controller, verify that the unit you are installing has the correct default settings. Failure to do so could result in a loss of features, such as ATC and PLC, or noncompliance with U.S. regulations such as FMVSS 121. It is recommended to use only the correct replacement part

number. However, most conguration settings can

be altered using the Bendix® ACom® ABS Diagnostic Software program.

Verify correct operation of the Bendix EC‑80 controller system and indicator lamps prior to putting the vehicle back into service. Towing vehicles manufactured after March 1, 2001 must support the trailer ABS indicator lamp located on the dash.

For further information, contact either the vehicle manufacturer, Bendix® or your local authorized Bendix® dealer.

1. Position and secure the Bendix EC‑80 controller in the original mounting orientation using the mounting bolts retained during removal. When mounting the unit in

the cab, use no more torque than is necessary to rmly

secure the ECU into position. Over‑tightening the mounting hardware can cause damage to the Bendix EC‑80 controller.

2. Reconnect the electrical connectors to the ECU.

3. Apply power and monitor the Bendix EC‑80 controller power‑up sequence to verify proper system operation.

See Troubleshooting: Wiring section beginning on page 32 for more information on wiring harnesses.

Troubleshooting: Blink Codes and Diagnostic Modes

ECU DIAGNOSTICS

The Bendix® EC‑80™ controller contains self‑testing diagnostic circuitry that continuously checks for the normal operation of internal components and circuitry, as well as external ABS components and wiring.

Active Diagnostic Trouble Codes

When an erroneous system condition is detected, the Bendix EC‑80 controller:

1. Illuminates the appropriate indicator lamp(s) and disengages part or all of the ABS and ATC functions. (See pages 8-9.)

2. Places the appropriate trouble code information in the ECU memory.

3. Communicates the appropriate trouble code information over the serial communications diagnostic link as required. Hand‑held or PC‑based diagnostic tools attach to the vehicle diagnostic connector, typically located on or under the dash (See Figure 7).

FIGURE 7 - TYPICAL VEHICLE DIAGNOSTIC CONNECTOR LOCATION (J1939)

BLINK CODES

Blink codes allow a technician to troubleshoot ABS problems without using a hand‑held or PC‑based diagnostic tool. Instead, information about the ABS system is communicated by the ECU using the ABS indicator lamp to display sequences of blinks.

Note: The ECU will not enter the diagnostic blink code mode if the wheel speed sensors show that the vehicle is in motion. If the ECU is in the diagnostic blink code mode and then detects vehicle motion, it will exit the blink code mode.

In addition, by operating the blink code switch as described below, one of several diagnostic modes can be entered. See Diagnostic Modes below.

Blink Code Switch Activation

When activating the blink code switch:

1. Wait at least two seconds after “ignition on.” (Except when

entering Reconguration Mode - see Reconguration

section on page 11)

2. For the ECU to recognize that the switch is activated “on,” the technician must press for at least 0.1 seconds, but less than 5 seconds. (If the switch is held for more than 5 seconds, the ECU will register a malfunctioning switch.)

3. Pauses between pressing the switch when a sequence is required, (e.g. when changing mode) must not be longer than 2 seconds.

4. After a pause of 3.5 seconds, the ECU will begin responding with output information blinks. See Figure 10 for an example.

FIGURE 8 - EXAMPLE OF BLINK CODE MESSAGE

Blink Code Timing

The ECU responds with a sequence of blink codes. The overall blink code response from the ECU is called a “message.” Each message includes, depending on the mode selected by the technician, a sequence of one or more groups of blinks. Simply record the number of blinks for each sequence and then use the troubleshooting index on page 18 for active or inactive trouble codes. Once you have located the code, you will be directed to the page that provides the applicable troubleshooting information.

NOTE:

1. Blink sequences illuminate the ABS indicator lamp for half a second, with half‑second pauses between them.

2. Pauses between blink code digits are 1.5 seconds.

3. Pauses between blink code messages are 2.5 seconds.

4. The lamp remains on for ve (5) seconds at the end of

messages.

See Figure 8 for an example showing the message: 2,1 followed by 2,2.

Once the ABS indicator lamp begins displaying a sequence of codes, it continues until all blink code messages have been displayed and then returns to the normal operating mode. During this time, the ECU will ignore any additional blink code switch activation.

All trouble codes, with the exception of voltage and J1939 trouble codes, will remain in an active state for the remainder of the power cycle.

Voltage trouble codes will clear automatically when the voltage returns within the required limits. All ABS functions will be re‑engaged.

J1939 trouble codes will clear automatically when communications are re‑established.

DIAGNOSTIC MODES

In order to communicate with the ECU, the controller has several modes that the technician can select, allowing information to be retrieved, or other ECU functions to be accessed.

Diagnostic Modes

To enter the various diagnostic modes:

No. of

Times to

Press the

Blink Code

Switch

1 Active Diagnostic Trouble Code (DTC) retrieval

2 Inactive DTC retrieval

3 Clear active DTCs

4 System conguration check

5 Dynamometer Test Mode

7* Recongure ECU

* To enter the Reconguration Mode, the switch must be held

in before the application of ignition power. Once the power is supplied, the switch is released and then pressed seven times.

CHART 3 - DIAGNOSTIC MODES

Active Diagnostic Trouble Code Mode

For troubleshooting, typically the active and inactive Diagnostic Trouble Retrieval Modes are used. The technician presses the blink code switch once and the ABS

indicator lamp ashes a rst group of two codes, and if

there are more trouble codes recorded, this is followed by a second set of codes, etc. (See page 18 for a directory of these codes.) All active trouble codes may also be retrieved using a hand‑held or PC‑based diagnostic tool, such as the Bendix® ACom® Diagnostics software.

To clear active DTCs (as problems are xed), simply clear

(or “self‑heal”) by removing and re‑applying ignition power. The only exception is for wheel speed sensor trouble codes, which clear when power is removed, re‑applied, and the ECU detects valid wheel speed from all wheel speed sensors. Alternately, codes may be cleared by pressing the diagnostic blink code switch three (3) times (to enter the Clear Active Diagnostic Trouble Code Mode) or by using a hand‑held or PC‑based diagnostic tool. Hand‑held or PC‑based diagnostic tools are able to clear wheel speed sensor trouble codes without the vehicle being driven.

System Mode Entered

Inactive Diagnostic Trouble Code Mode

The ECU stores past trouble codes and comments (such

as conguration changes) in its memory. This record is

commonly referred to as “event history.” When an active trouble code is cleared, the ECU stores it in the event history memory as an inactive trouble code.

Using blink codes, the technician may review all inactive trouble codes stored on the ECU. The ABS indicator

lamp will display inactive diagnostic blink codes when the diagnostic blink code switch is depressed and released two times. See page 18 for the index showing trouble codes.

Go to the specic troubleshooting guide page shown there

for further help.

Inactive trouble codes and event history may be retrieved and cleared by using a hand‑held or PC‑based diagnostic tool, such as the Bendix® ACom® Diagnostics software.

Clearing Active Diagnostic Trouble Codes

The ECU will clear active trouble codes when the diagnostic blink code switch is depressed and released three (3) times.

System Conguration Check Mode

The ABS indicator lamp will display system conguration

information when the diagnostic blink code switch is depressed and released four (4) times. The lamp will blink

out conguration information codes using the following

patterns. (See Chart 4).

1st Number System Power

1 12 Volts

2 24 Volts

2nd Number Wheel Speed Sensors

4 4 Sensors

6 6 Sensors

3rd Number Pressure Modulator Valves

4 4 Modulators

5 5 Modulators

6 6 Modulators

4th Number ABS Conguration

1 4S/4M or 6S/6M

2 6S/4M

3 6S/5M

5th Number Traction Control Conguration

2 No ATC

3 ATC Engine Control Only

4 ATC Brake Control Only

5 Full ATC (Engine Control & Brake Control)

6th Number Retarder Conguration

1 No Retarder

2 J1939 Retarder

3 Retarder Relay

4 J1939 Retarder, Retarder Relay

CHART 4 - SYSTEM CONFIGURATION CHECK

In this mode, the ECU tells the technician — by means of a series of six blink codes — the type of ABS system that the ECU has been set up to expect. For example, if the fourth blink code seqiemce is a three, the technician knows

that a 6S/5M sensor/modulator conguration has been set.

Dynamometer Test Mode

The Dynamometer Test Mode is used to disable ATC when needed (e.g. when performing any vehicle maintenance where the wheels are lifted off the ground and moving, including dyno testing). This mode is not reset by power off, power on cycling. Instead a hand‑held or PC‑based diagnostic tool must be used to change the setting. Alternatively, depressing and releasing the blink code switch three times will cause the ECU to exit the blink code mode.

Recongure ECU Mode

Vehicle reconfiguration is carried out by using the

Recongure ECU Mode. (See page 11.) Note: To enter the Reconguration Mode, the blink code switch must be

held in before the application of ignition power. Once the power is supplied, the switch is released and then pressed seven times.

Troubleshooting: Using Hand-Held or

PC-Based Diagnostic Tools

USING HAND-HELD OR PC-BASED DIAGNOSTICS

Troubleshooting and Diagnostic Trouble Code (DTC)

clearing (as well as reconguration) may also be carried out

using hand‑held or PC‑based diagnostic tools such as the Bendix® Remote Diagnostic Unit (RDU™), Bendix® ACom® Diagnostics software, or the ProLink™ tool.

LED lights

illuminate

Diagnostic

Trouble

Codes

(10 locations

in total)

FIGURE 9 - THE BENDIX® REMOTE DIAGNOSTIC UNIT (RDU)

Bendix® RDU™ (Remote Diagnostic Unit)

The Bendix® RDU™ tool provides the technician with a visual indication of Antilock Braking System (ABS) component Diagnostic Trouble Code (DTC) information.

The RDU tool is specically designed for use with Bendix®

ABS systems and Bendix makes no claims for its operation and/or usability with other brands of ABS systems.

Features of the Bendix® RDU™ Tool

The RDU tool attaches to the 9 pin diagnostic connector in the cab of the vehicle. An adapter cable (Bendix part number 5012793) is available to connect the RDU to vehicles with a 6‑pin diagnostic connector. (See Figure 9.)

The RDU tool allows the technician to:

• Troubleshoot ABS system component problems using

DTC reporting via LEDs.

• Reset DTCs on Bendix ABS ECUs by holding a magnet

over the reset in the center of the RDU tool for less than 6 seconds.

• Enter the Self-Conguration Mode used by Bendix ABS

ECUs by holding a magnet over the reset area for greater than 6 seconds but less than 30 seconds.

How the Bendix RDU Operates

See Figure 7 for typical vehicle connector locations.

When the RDU tool is plugged into the diagnostic connector, all the LEDs will illuminate, and the green LED

will ash four (4) times to indicate communications have

been established.

If the ABS ECU has no active DTCs, only the green LED will remain illuminated.

If the ABS ECU has at least one active DTC the RDU

tool displays the rst DTC by illuminating the red LEDs,

indicating the malfunctioning ABS component and its location on the vehicle. (See Figure 10.) If there are multiple DTCs on the ABS system, the RDU tool will display

one DTC rst, then once that DTC has been repaired and

cleared, the next code will be displayed.

Typical Combination DTCs are:

• Right steer sensor

• Left steer sensor

• Right drive sensor

• Left drive sensor

• Right additional sensor

• Left additional sensor

• Right steer modulator

• Left steer modulator

• Right drive modulator

• Left drive modulator

• Right additional

modulator

• Left additional

modulator

• Traction modulator

• ECU

• Engine serial

communication

• MOD red LED illuminated, shows the “Common”

connection of one or more modulators is shorted to battery or ground

• VLT (Flashing indicates either over‑ or under‑voltage

condition)

To pinpoint the root cause and to ensure that the system DTC has been properly corrected, additional troubleshooting may be necessary.

Bendix® RDU™ Reset Function

The magnetic reset switch is located in the center top of the RDU tool. Activation requires a magnet with 30 gauss minimum.

The reset operations are:

1. If the magnet is held over the switch for less than six (6) seconds the “clear Diagnostic Trouble Codes” command is sent.

2. If the magnet is held over the switch for more than six (6) seconds, but less than 30 seconds, the Bendix ABS

“self-conguration command” is sent.

Additionally, it is recommended at the end of any inspection that the user switches off and restores the power to the ABS ECU, then check the ABS indicator lamp operation and RDU™ tool to see if they indicate any remaining DTCs.

LED Diagnostic Trouble Codes

LFT ‑ Left RHT ‑ Right DRV ‑ Drive Axle ADD ‑ Additional STR ‑ Steer Axle VLT ‑ Power

ECU ‑ ABS Controller SEN ‑ Wheel Speed Sensor MOD ‑ Pressure Modulator Valve TRC ‑ Traction Control

Example: If the Diagnostic Trouble Code is “Right Steer Axle Sensor”, the RDU™ unit will display one green and three red LEDs

FIGURE 10 - DIAGNOSTIC TROUBLE CODES

LEDs

Green

VLT

Red SEN STR RHT

Bendix® RDU™ Communication Problems

If the ABS ECU does not respond to the RDU tool’s request for Diagnostic Trouble Codes, the RDU tool will illuminate each red LED in a clockwise pattern. This pattern indicates the loss of communication and will continue until the ABS ECU responds and communication has been re‑established.

Possible sources of communication problems are:

1. A problem with the J1939 link at the in‑cab off‑board diagnostic connector (9‑Pin).

2. The ECU does not support PID194.

3. No power is being supplied to the ECU and/or the diagnostic connector.

4. The J1939 bus is overloaded with information and the RDU can not arbitrate access.

5. A malfunctioning RDU tool.

Bendix® ACom® Diagnostics Software

Bendix® ACom® Diagnostics is a PC‑based software program and is designed to meet RP‑1210 industry standards. This software provides the technician with access to all the available ECU diagnostic information and

conguration capability, including:

• ECU information

• Diagnostic trouble codes and repair information

• Conguration (ABS, ATC, and more)

• Wheel speed information

• Perform component tests

• Save and print information

FIGURE 11 - BENDIX® ACOM® DIAGNOSTICS

When using ACom® Diagnostics software to diagnose the Bendix® EC‑80™ ABS ECU, the computer’s serial, parallel or USB port needs to be connected to the vehicle’s diagnostic connector.

For more information on ACom Diagnostics software or RP1210 compliant tools, go to www.bendix.com or visit your local authorized Bendix parts outlet.

See pages 40-43 for Appendix: J1939 SPN and FMI codes and their Bendix blink code equivalents.

www.bendix.com

For the latest information, and for free downloads of the Bendix ACom Diagnostics software, and its User Guide, visit the Bendix website at www.bendix.com.

Bendix Technical Assistance Team

For direct telephone technical support, call the Bendix technical assistance team at:

1-800-AIR-BRAKE (1‑800‑247‑2725, option 2,1), Monday through Friday, 8:00 A.M. to 6:00 P.M. ET, and follow the instructions in the recorded message. Or, you may send an e‑mail to techteam@bendix.com to reach the Bendix technical assistance team.

Active or Inactive

Diagnostic Trouble Code

INDEX

How to interpret the rst digit of messages received when active

or inactive Diagnostic Trouble Code (DTC) Mode is entered.

1st Blink Code Number

1 ............................................... No DTCs (1,1)

2 ............ Wheel Speed Sensors ‑ page 19‑20

3 ............ Wheel Speed Sensors ‑ page 19‑20

4 ............ Wheel Speed Sensors ‑ page 19‑20

5 ............ Wheel Speed Sensors ‑ page 19‑20

6 ................................ Power Supply ‑ page 24

7 ...... Pressure Modulator Valves ‑ page 21‑22

8 ...... Pressure Modulator Valves ‑ page 21‑22

9 ...... Pressure Modulator Valves ‑ page 21‑22

10..... Pressure Modulator Valves ‑ page 21‑22

11 ..... J1939 Serial Communications ‑ page 25

12........................ Miscellaneous ‑ page 27‑29

13............................................. ECU ‑ page 26

14........... Wheel Speed Sensors ‑ page 19‑20

15........... Wheel Speed Sensors ‑ page 19‑20

16..... Pressure Modulator Valves ‑ page 21‑22

17..... Pressure Modulator Valves ‑ page 21‑22

18................ Traction Control Valves ‑ page 23

Go Here for Troubleshooting Tests

Example: For a message sequence of:

3, 2 12, 4

For the rst sequence go to page 19 and

for the second sequence go to page 27.

See Page 40 for Appendix: J1939 SPN and FMI Codes and their Bendix® Blink Code Equivalents

www.bendix.com

For the latest information, and for free downloads of the Bendix® ACom® Diagnostics software, and its User Guide, visit the Bendix website at www.bendix.com.

Bendix Technical Assistance Team

For direct telephone technical support, call the Bendix technical assistance team at: 1-800-AIR-BRAKE (1‑800‑247‑2725 option 2, then 1), Monday through Friday, 8:00 A.M. to 6:00 P.M. ET, and follow the instructions in the recorded message. Or, you may e‑mail the Bendix technical assistance team at: techteam@bendix.com.

Troubleshooting Diagnostic Trouble Codes:

Wheel Speed Sensors

1st. Blink

Code

2 Left Steer Axle Sensor

3 Right Steer Axle Sensor

4 Left Drive Axle Sensor

5 Right Drive Axle Sensor

14 Left Additional Axle Sensor

15 Right Additional Axle Sensor

Location

2nd. Diagnostic

Blink Trouble Code Code Description

1 Excessive Air Gap

2 Output Low at Drive‑off

3 Open or Shorted

Repair Information

Adjust sensor to contact exciter ring. Rotate wheel and verify a minimum of 0.25 VAC sensor output at ~ 0.5 RPS. Verify condition of sensor head. Verify mounting of exciter ring and condition of teeth. Verify proper bearing end‑play. Verify condition and retention of clamping sleeve. Verify sensor lead routing and clamping.

Verify 1500 – 2500 ohms across sensor leads. Verify no continuity between sensor leads and ground or voltage. Verify no continuity between sensor leads and other sensors. Check for corroded/damaged wiring or connectors between the ECU and the wheel speed sensor.

4 Loss of Sensor Signal

5 Wheel End

6 Erratic Sensor Signal

7 Tire Size Calibration

10 Conguration

Error

Adjust sensor to contact exciter ring. Rotate wheel and verify a minimum of

0.25 VAC sensor output at ~ 0.5 RPS. Verify condition of sensor head. Verify mounting of exciter ring and condition of teeth. Verify proper bearing end‑play. Verify condition and retention of clamping sleeve. Verify sensor lead routing and clamping. Check for corroded/damaged wiring or connectors between the ECU and the wheel speed sensor.

Verify mounting of exciter ring and condition of teeth. Verify proper bearing end‑ play. Verify condition and retention of clamping sleeve. Verify sensor lead routing and clamping. Check mechanical function of brake. Check for kinked or restricted air lines.

Adjust sensor to contact exciter ring. Rotate wheel and verify a minimum of

Verify correct tire size as desired. Verify proper tire ination. Verify correct number

of exciter ring teeth.

ECU is congured for four sensors, but has detected the presence of additional sensors. Verify sensor wiring and ECU conguration.

Speed Sensor Repair Tests:

1. Take all measurements at ECU harness connector pins in order to check wire harness and sensor. Probe the connector carefully so that the terminals are not damaged.

2. Wheel speed sensor measurements should read:

Location Measurement

Sensor 1500 - 2500 Ohms

Sensor to voltage or ground Open Circuit (no continuity)

Sensor output voltage >0.25 of VAC sensor output at ~ 0.5 revs/sec.

3. Clear DTC after issue is corrected. The dynamic sensor DTC will remain until the power is cycled to the ABS ECU and vehicle is driven above 15 MPH or DTC was cleared using either the diagnostic blink code switch or diagnostic tool.

Cab-mount ECU: Looking into wire harness connector

Connector Pin Wheel Speed Sensor Location

18 Way

15 Way (if Bendix®

EC-80™ ATC ECU

is conﬁgured for 6

sensors)

10 Right Drive Axle (+)

11 Right Drive Axle (-)

5 Left Steer Axle (+)

8 Left Steer Axle (-)

11 Right Steer Axle (+)

14 Right Steer Axle (-)

15 Left Drive Axle (+)

18 Left Drive Axle (-)

11 Left Additional Axle (+)

14 Left Additional Axle (-)

12 Right Additional Axle (+)

15 Right Additional Axle (-)

Troubleshooting Diagnostic Trouble Codes:

Pressure Modulator Valves

1st. Blink

Code

7 Left Steer Axle

8 Right Steer Axle

9 Left Drive Axle

10 Right Drive Axle

16 Left Additional Axle

17 Right Additional Axle

Location

2nd. Diagnostic

Blink Trouble Code Code Description

1 Release Solenoid Shorted to Ground

2 Release Solenoid Shorted to Voltage

3 Release Solenoid Open Circuit

Repair Information

Verify no continuity between PMV leads and ground. Verify 4.9 to 5.5 ohms from REL to CMN & HLD to CMN, and 9.8 to 11 ohms from REL to HLD. Check for corroded/damaged wiring or connectors between ECU and PMV.

Verify no continuity between PMV leads and voltage. Verify 4.9 to 5.5 ohms from REL to CMN & HLD to CMN, and 9.8 to 11 ohms from REL to HLD. Check for corroded/damaged wiring or connectors between ECU and PMV.

Verify 4.9 to 5.5 ohms from REL to CMN & HLD to CMN, and 9.8 to 11 ohms from REL to HLD. Check for corroded/damaged wiring or connectors between ECU and PMV.

4 Hold Solenoid Shorted to Ground

5 Hold Solenoid Shorted to Voltage

6 Hold Solenoid Open Circuit

7 CMN Open Circuit

8 Conguration

Error

Verify 4.9 to 5.5 ohms from REL to CMN & HLD to CMN, and 9.8 to 11 ohms from REL to HLD. Check for corroded/damaged wiring or connectors between the ECU and PMV.

A mis-match exists between the ECU conguration and the modulator installation and wiring. Verify PMV wiring and installation. Verify ECU conguration.

Pressure Modulator Valve Repair Tests:

1. Take all measurements at ECU harness connector pins in order to check wire harness and PMV. Probe the connector carefully so that the terminals are not damaged.

2. Pressure modulator resistance should read:

Location Measurement

Release to Common 4.9 to 5.5 Ohms

Hold to Common 4.9 to 5.5 Ohms

Release to Hold 9.8 to 11.0 Ohms

Release, Hold, Common Open Circuit (no continuity) to Voltage or Ground

When troubleshooting modulator trouble codes, check inactive trouble codes and event history for over-voltage or trouble codes. If one of these is found, troubleshoot

these trouble codes rst, before the PMV.

Cab-mount ECU: Looking into wire harness connector

Connector Pin PMV Location

1 Left Steer Axle Hold

2 Left Steer Axle Release

3 Left Steer Axle Common

4 Right Steer Axle Hold

6 Right Steer Axle Common

18 Way

15 Way (if Bendix®

EC-80™ ATC ECU

is conﬁgured for 6

sensors)

7 Right Steer Axle Release

9 Right Drive Axle Common

10 Right Drive Axle Hold

13 Right Drive Axle Release

12 Left Drive Axle Common

16 Left Drive Axle Hold

17 Left Drive Axle Release

4 Left Additional Axle Hold

6 Left Additional Axle Common

7 Left Additional Axle Release

9 Right Additional Axle Common

10 Right Additional Axle Hold

13 Right Additional Axle Release

Troubleshooting Diagnostic Trouble Codes:

Traction Control Valves

1st. Blink

Code

18 Traction Control Valve

Location

2nd. Diagnostic

Blink Trouble Code Code Description

1 TCV Solenoid Shorted to Ground

2 TCV Solenoid Shorted to Voltage

3 TCV Solenoid Open Circuit

Repair Information

Verify 7 to 19 ohms between TCV and TCV common. Verify no continuity between TCV leads and ground. Check for corroded/damaged wiring or connectors between ECU and TCV.

Verify 7 to 19 ohms between TCV and TCV common. Verify no continuity between TCV leads and voltage. Check for corroded/damaged wiring or connectors between ECU and TCV.

Verify 7 to 19 ohms between TCV and TCV common. Check for corroded/damaged wiring or connectors between ECU and TCV.

4 TCV

Conguration

Error

The ECU is not congured for ATC, but has detected the presence of a TCV. Verify TCV wiring. Inspect for the presence of a TCV. Verify ECU conguration.

Automatic Traction Control Valve Inspections should include:

• Looking for kinked air hoses, inside the harness socket for removed or corroded connector pins; and a test to verify that the ATC valve solenoids are functioning correctly.

Repair Tests:

1. Take all measurements at ECU harness connector pins in order to check wire harness and traction control valve. Probe the connector carefully so that the terminals are not damaged.

2. Tractor Control Valve resistance measurements should read:

Location Measurement

TCV to TCV Common 7 to 19 Ohms

TCV or TCV Common Open Circuit (no continuity) to Voltage or Ground

Cab-mount ECU:

Looking into wire harness connector

Connector Pin Traction Control Test

X1 4 Traction Control Valve Common

18 Way 5 Traction Control Valve

Troubleshooting Diagnostic Trouble Codes: Power Supply

1st. Blink

Code

6 Power Supply

Location

2nd. Diagnostic

Blink Trouble Code Code Description

1 Battery Voltage Too Low

2 Battery Voltage Too High

Measure battery voltage under load. Check vehicle battery and associated components. Check for damaged wiring. Check for damaged or corroded connectors and connections.

Measure battery voltage under load. Ensure that battery voltage is correct for the ECU. Check vehicle battery and associated components. Check for damaged wiring. Check for damaged or corroded connectors and connections.

Power Supply Tests:

1. Take all measurements at ECU harness connector.

2. Place a load (e.g. an 1157 stop lamp) across battery or ignition and ground connection, measure ignition and battery voltage with the load. Ignition‑to‑Ground should measure between 9 to 17 VDC. Battery‑to‑ Ground should also measure between 9 to 17 VDC.

Repair Information

3. Check for damaged wiring, damaged or corroded connectors and connections.

4. Check condition of vehicle battery and associated components, ground connection good and tight.

5. Check alternator output for excessive noise.

Cab-mount ECU: Looking into wire harness connector

Connector Pin Power Supply Test

X1 1 Ground 18 Way 3 Ignition 16 Battery

Troubleshooting Diagnostic Trouble Codes:

J1939 Serial Communications

1st. Blink

Code

11 J1939

2nd. Blink Code

1 J1939 Serial

2 J1939 Electronic

3 J1939 Electronic

4 J1939 Electronic

10 J1939 Transmission

Location

Diagnostic Trouble

Code Description

Link Loss of Communications

Retarder Timeout or Invalid Signal (ERC1)

Engine Controller 1, Timeout or Invalid Signal (EEC1)

Engine Controller 2 Timeout or Invalid Message (EEC2)

Loss of Communications, ETC1 Message

Repair Information

Loss of communications between the Bendix® EC‑80™ controller and other devices connected to the J1939 link. Check for damaged or reversed J1939 wiring. Check for

corroded or damaged connectors. Verify ECU Conguration. Check for other devices

inhibiting J1939 communications.

Check for damaged or reversed J1939 wiring. Check for corroded or damaged connectors.

Verify presence of retarder on the J1939 link. Verify ECU Conguration. Verify that the retarder is congured to broadcast ERC1. Check for other devices inhibiting J1939

communications.

Check for damaged or reversed J1939 wiring. Check for corroded or damaged connectors.

Verify presence of ECU on the J1939 link. Verify ECU Conguration. Verify the ECU is congured to broadcast EEC1. Check for other devices inhibiting J1939 communications.

Check for damaged or reversed J1939 wiring. Check for corroded or damaged connectors.

Verify presence of Engine ECU on the J1939 link. Verify ECU Conguration. Verify that there is an EEC2 broadcast from the address congured in the ABS ECU. Check for other

devices inhibiting J1939 communications.

Loss of communications between the Bendix EC‑80 controller and the transmission ECU over the J1939 link. Check for damaged or reversed J1939 wiring. Check for corroded or damaged connectors. Verify presence of engine ECU on the J1939 link. Verify ECU

Conguration. Check for other devices inhibiting J1939 communications.

15 J1939 Engine Loss

of Communications, EEC3 Message

16 J1939 Engine Loss

of Communications, ETC2 Message

Loss of communications between the Bendix EC‑80 controller and the engine ECU over the J1939 link. Check for damaged or reversed J1939 wiring. Check for corroded or damaged

connectors. Verify presence of engine ECU on the J1939 link. Verify ECU Conguration.

Check for other devices inhibiting J1939 communications.

Conguration. Check for other devices inhibiting J1939 communications.

J1939 Troubleshooting Tests:

1. Take all measurements at ECU harness connector.

2. Check for damaged or reversed J1939 wiring.

Cab-mount ECU:

Looking into wire harness connector

Connector Pin J1939

X1 7 J1939 Low

18 Way 8 J1939 High

3. Check for corroded or damaged wiring connector problems such as opens or shorts to voltage or ground.

4. Check for other J1939 devices which may be loading down (inhibiting) J1939 communication.

Troubleshooting Diagnostic Trouble Codes:

ECU

1st. Blink

Code

13 ECU

Location

2nd Blink Code

10 ECU DTC (5FC)

11 ECU DTC (F1A)

12 ECU DTC (F14)

14 ECU DTC (C6)

Diagnostic Trouble Code Description

(With HEX designation)

1 ECU DTC (5F3)

2 ECU DTC (5CD)

4 ECU DTC (2678C)

5 ECU DTC (1C)

6 ECU DTC (6CD)

8 ECU DTC (56)

9 ECU DTC (CAC3)

ECU DTC (10)

Conguration

mismatch

Conguration

mismatch

Repair Information

Check for damaged or corroded connectors. Check for damaged wiring. Clear trouble codes. If Diagnostic Trouble Codes return, contact the Bendix Tech Team at 1‑800‑AIR‑BRAKE (1‑800‑247‑2725, option 2, then 1) for further troubleshooting assistance.

Verify components installed match ECU conguration

Check for damaged or corroded connectors. Check for damaged wiring. Clear trouble codes. If Diagnostic Trouble Codes return, contact the Bendix Tech Team at 1‑800‑AIR‑BRAKE (1‑800‑247‑2725 , option 2, then 1) for further troubleshooting assistance.

Verify components installed match ECU conguration

15 ECU DTC (CF)

16 ECU DTC (C0)

17 ECU DTC (C8C)

18 ECU DTC (CC)

19 ECU DTC (63)

20 ECU DTC (6E)

21 ECU DTC (6C)

22 ECU DTC (63C)

Valve Conguration

Mismatch

Check for damaged or corroded connectors. Check for damaged wiring. Clear trouble codes. If Diagnostic Trouble Codes return, contact the Bendix Tech Team at 1‑800‑AIR‑BRAKE (1‑800‑247‑2725 , option 2, then 1) for further troubleshooting assistance.

Verify number of modulators wired matches components installed

match ECU conguration

Troubleshooting Diagnostic Trouble Codes: Miscellaneous

1st. Blink

Code

Location

12 Miscellaneous

2nd. Blink Code

Diagnostic Trouble Code Description

Stop Lamp Switch Not Detected

Stop Lamp Switch Defective

ATC Disabled or Dynamometer Test Mode Active

Repair Information Repair Information

ECU has not detected the presence of the stop lamp switch since ignition power was applied (note that stop lamp switch input may be applied to the Bendix® EC‑80™ controller using either hardwire input or J1939). Apply and release service brake. Check for brake switch input into ECU (see system wiring schematic). With service brake released, check for presence of the stop lamp bulb. With service brake applied, verify system voltage is now present at the stop lamp switch input to the ECU. Check for damaged wiring between ECU, stop lamp switch and bulb. Check for corroded or damaged connectors. Check for damaged or reversed J1939 wiring. Check for corroded or damaged connectors on J1939 link. Verify

presence of engine ECU on the J1939 link. Verify ECU conguration.

Apply and release service brake. Check for brake switch input into ECU (see system wiring schematic). With service brake released, check for presence of the stop lamp bulb. With service brake applied, verify system voltage is now present at the stop lamp switch input to the ECU. Check for damaged wiring between ECU, stop lamp switch and bulb. Check for corroded or damaged connectors. Check for damaged or reversed J1939 wiring. Check for corroded or damaged connectors on J1939 link. Verify presence of engine ECU on the

J1939 link. Verify ECU conguration.

ECU has been placed in the Dynamometer Test Mode by either the diagnostic blink code switch or a hand‑held or PC‑based diagnostic tool. ATC is disabled.

Retarder Relay Open Circuit or Shorted to Ground

Retarder Relay Circuit Shorted to

Verify vehicle contains a retarder relay. Verify ECU conguration. Check wiring between

ECU and retarder relay. Verify no continuity between retarder disable output of Bendix EC‑80 controller and ground. Verify condition and wiring of the retarder relay.

Check wiring between ECU and retarder relay. Verify no continuity between retarder disable output of Bendix EC‑80 controller and voltage. Verify condition and wiring of the retarder relay.

Voltage

ABS Indicator Lamp Circuit Fault

Common Shorted to Ground

Check operation of diagnostic blink code switch. Check wiring of diagnostic blink code switch, and ABS WL. Verify ABS WL ground input.

Verify no continuity between the CMN of all PMVs, (HSA, TCV, and Diff Lock Solenoid — Bendix EC‑80 ATC options) and ground. Check for corroded/damaged wiring or connectors between the ECU and CMN of all PMVs, (HSA, TCV, and Diff Lock Solenoid — Bendix EC‑80 ATC options).

Common Shorted to Voltage

Verify no continuity between the CMN of all PMVs, (HSA, TCV, and Diff Lock Solenoid — Bendix EC‑80 ATC options) and voltage. Check for corroded/damaged wiring or connectors between the ECU and CMN of all PMVs, (HSA, TCV, and Diff Lock Solenoid — Bendix EC‑80 ATC options).

ATC Disabled

ATC is temporarily disabled to prevent excessive heating of the foundation brakes. to Prevent Brake Fade

Wheel Speed Sensors Reversed

Sensors are reversed (left to right) on one of the axles. Verify proper installation, connection,

and wiring of the sensors. on an Axle

Diff. Lock Solenoid Shorted to Ground or Open Circuit

Verify no continuity between the Diff Lock Solenoid and ground. Check for corroded/damaged

wiring or connectors between the ECU and Diff Lock Solenoid.

Troubleshooting Diagnostic Trouble Codes: Miscellaneous

1st. Blink

Code

12 Miscellaneous

2nd. Blink Code

Location

Diagnostic Trouble Code Description

Diff. Lock Solenoid Shorted to Voltage

ABS disabled due to off‑road mode

Maximum number of PMV cycles exceeded

Maximum Number of TCV Cycles Exceeded

ABS Disabled Due to Engaged Interlock

I/O 3 Shorted High Check for short circuit condition between voltage and the I/O 3 circuit. Verify the resistance

Repair Information

Verify no continuity between the Diff Lock Solenoid and voltage. Check for corroded/damaged wiring or connectors between the ECU and Diff Lock Solenoid.

The ABS indicator lamp will be ashing, indicating the ECU is in the off-road ABS mode.

Remove and re‑apply ignition power.

Replace all PMV valves and clear the DTC.

Replace all TCV valves and clear the DTC.

The ABS indicator lamp will be ashing to indicate that the ECU is in the ABS Off-road Mode.

Remove and re‑apply ignition power.

between the Input/Output and voltage is open.

HSA Lamp Open Circuit or Shorted to GND

HSA Valve Solenoid is Shorted to GND

HSA Valve Sole‑ noid is Shorted to Voltage

Air system/ Mechanical Component

HSA Lamp Shorted to Voltage

HSA Lamp Sole‑ noid Open Circuit

Verify that the resistance measured between the battery and HSA lamp output of the ECU is open. Check the wiring between the ECU and the HSA lamp. Check the condition and wiring of the HSA lamp.

Verify that there is no resistance measured between ground and the HSA solenoid. Check for corroded or damaged wiring or connectors between the ECU and the HSA solenoid.

Verify that there is no resistance measured between voltage and the HSA solenoid. Check for corroded or damaged wiring or connectors between the ECU and the HSA solenoid.

Verify brakes are operating correctly. Verify that there is not over‑braking at one or more wheel end(s). Check the pneumatic plumbing and the exhaust port of the PCVs, TCVs, and

relay valves and conrm that the air is being exhausted from all brake chambers. Verify tire sizes on the vehicle match the ABS ECU conguration. Verify wheel speed sensors and

tone ring are properly adjusted and in good condition.

Verify tires are in good condition. Verify pneumatic hoses are not twisted or kinked. Verify that the brakes are operating correctly. Verify that the wheel speed sensor and tone ring are properly adjusted. Verify tire size.

Verify that there is no resistance measured between the battery and HSA lamp output of the ECU. Check the wiring between the ECU and HSA lamp. Check the HSA lamp and condition of its wiring.

Verify resistance across the HSA solenoid. Check the ECU and HSA solenoid for corroded or damaged wiring and/or connectors.

Miscellaneous Troubleshooting

For all tests below, take all measurements at ECU harness connector pins in order to check wire harness and sensor. Probe the connector carefully so that the terminals are not damaged.

Stop Lamp Switch Test

1. With the service brake applied, measure the system voltage (9 to 17 VDC) stop lamp switch input to ECU.

Test Measurement

Stop Lamp Switch to Ground 9 to 17 VDC

2. Apply and release service brake, does lamp extinguish?

3. Verify brake lamp switch is connected to ECU via hard wire or J1939.

4. With service brake released, check for presence of stop lamp bulb.

Dynamometer Test Mode (ATC Indicator Lamp Continuously Illuminated)

1. Clear the Dynamometer Test Mode by depressing and releasing the blink code switch three times (or use an off‑board diagnostic tool).

ABS Indicator Lamp

1. Verify diagnostic blink code switch is open when not activated.

Retarder Relay

1. Measure resistance between retarder disable output of Bendix® EC‑80™ controller and voltage / ground.

Test Measurement

Retarder disable to Voltage Open Circuit (no continuity) or Ground

2. Verify vehicle has retarder relay.

3. Verify proper wiring from ECU to retarder relay.

PMV Commons

1. Measure resistance between any common (PMV, TCV, and Diff.) and voltage or ground.

Test Measurement

Any PMV, TCV, or Diff. Open Circuit (no continuity) Common to Voltage

or Ground

Differential Lock Solenoid

1. Measure resistance between Diff lock solenoid and voltage or ground.

Test Measurement

Diff. Lock Solenoid to Voltage Open Circuit (no continuity) or Ground

Cab-mount ECU: Looking into wire harness connector

Connector Pin PMV Location

4 TCV Common

X1 9 Stop Lamp Switch

18 Way 12 ABS WL Ground

15 ABS WL Interlock

17 Retarder

18 ABS WL

3 PMV Left Steer Axle Common

X2 6 PMV Right Steer Axle Common

18 Way 9 PMV Right Drive Axle Common

12 PMV Left Drive Axle Common

2 Diff Lock Solenoid

X3 3 Diff Lock Solenoid Common

15 Way 6 PMV Left Additional Axle Common

9 PMV Right Additional Axle Common

Troubleshooting: Connectors and Harnesses

Bendix® EC-80™ ABS Controller Wire Harness Connector Part Numbers and Pin Assignments: Bendix EC-80 ABS CAB

X1 X2

Bendix EC-80 ABS Controller

Bendix EC-80 ABS versions utilize two AMP connectors for wire harness connections.

Connectors

not used

Connector Designation Number of Contacts AMP Part Number

X1 17 1718091-1

X2 18 8-968974-1

Bendix EC-80 ABS X1 Connector Pin Assignments

Pin Designation Pin Designation Pin Designation

1 Ground 7 J1939 Low 13 Not Used

2 Trailer ABS WL 8 J1939 High 14 Not Used

3 Ignition 9 Not Used 15 ABS WL Interlock

4 Not Used 10 WSS DA Right (+) 16 Battery

5 Not Used 11 WSS DA Right (-) 17 Retarder

6 Not Used 12 ABS WL Ground 18 ABS WL

Bendix EC-80 ABS X2 Connector Pin Assignments

Pin Designation Pin Designation Pin Designation

1 PMV SA Left HLD 7 PMV SA Right REL 13 PMV DA Right REL

2 PMV SA Left REL 8 WSS SA Left (-) 14 WSS SA Right (-)

3 PMV SA Left CMN 9 PMV DA Right CMN 15 WSS DA Left (+)

4 PMV SA Right HLD 10 PMV DA Right HLD 16 PMV DA Left HLD

5 WSS SA Left (+) 11 WSS SA Right (+) 17 PMV DA Left REL

6 PMV SA Right CMN 12 PMV DA Left CMN 18 WSS DA Left (-)

Troubleshooting: Connectors and Harnesses

(Continued)

Bendix® EC-80™ ATC Controller Wire Harness Connector Part Numbers and Pin Assignments:

X1 X4X2 X3

Bendix EC-80 ATC Controller

Bendix EC‑80 ATC versions utilize three AMP connectors for wire harness connections.

Connector Designation Number of Contacts AMP Part Number

X1 17 1718091-1

X2 18 8-968974-1

X3 15 8-968973-1

Connector

not used

Bendix EC-80 ATC X1 Connector Pin Assignments

Pin Designation Pin Designation Pin Designation

1 Ground 7 J1939 Low 13 Not Used

2 Trailer ABS WL 8 J1939 High 14 Not Used

3 Ignition 9 SLS 15 ABS WL Interlock

4 TCV CMN 10 WSS DA Right (+) 16 Battery

5 TCV 11 WSS DA Right (-) 17 Retarder

6 ATC Lamp/ATC ORS 12 ABS WL Ground 18 ABS WL

Bendix EC-80 ATC X2 Connector Pin Assignments

Pin Designation Pin Designation Pin Designation

1 PMV SA Left HLD 7 PMV SA Right REL 13 PMV DA Right REL

2 PMV SA Left REL 8 WSS SA Left (-) 14 WSS SA Right (-)

3 PMV SA Left CMN 9 PMV DA Right CMN 15 WSS DA Left (+)

4 PMV SA Right HLD 10 PMV DA Right HLD 16 PMV DA Left HLD

5 WSS SA Left (+) 11 WSS SA Right (+) 17 PMV DA Left REL

6 PMV SA Right CMN 12 PMV DA Left CMN 18 WSS DA Left (-)

Bendix EC-80 ATC X3 Connector Pin Assignments

Pin Designation Pin Designation Pin Designation

1 ABS ORS 6 PMV AA Left CMN 11 WSS AA Left (+)

2 Diff. Lock SOL1 7 PMV AA Left REL 12 WSS AA Right (+)

3 Diff. Lock SOL CMN1 8 Input/Output 3 13 PMV AA Right REL

4 PMV AA Left HLD 9 PMV AA Right CMN 14 WSS AA Left (-)

5 Input/Output 2 10 PMV AA Right HLD 15 WSS AA Right (-)

1AWD vehicles only. (AWD Transfer Case)

ABS/ATC WIRING

Troubleshooting: Wiring

ECU Wiring Harness Connectors

Bendix® EC‑80™ controllers are designed to interface with AMP MCP 2.8 connectors as referenced in Chart 4. Follow all AMP requirements for the repair of wire harnesses.

All wire harness connectors must be properly seated. The use of secondary locks is strongly advised.

All unused ECU connectors must be covered and receive proper environmental protection.

ABS Wiring Requirements

As a matter of good practice and to ensure maximum system robustness, always use the maximum size wire supported by the wire harness connectors for battery, ignition, ground, PMV, TCV, Interaxle Differential Lock and indicator lamp circuits.

All sensor and serial communications circuits (J1939) must use twisted pair wiring (one to two twists per inch). See the appropriate SAE document for additional details.

All wires must be carefully routed to avoid contact with rotating elements. Wiring must be properly secured approximately every 6 to 12 inches using UV stabilized, non‑metallic hose clamps or bow‑tie cable ties to prevent pinching, binding or fraying.

It is recommended that wires be routed straight out of a connector for a minimum of three inches before the wire is allowed to bend.

Battery and ground wires should be kept to a minimum length.

If convoluted tubing is used, its I.D. must match the size of the wire bundle as closely as possible.

Wire harness lengths must be carefully selected for the vehicle. Harnesses that are too long increase the possibility of electrical interference and wire damage. Excess lengths of wire are not to be wound to form coils, instead re-route, repair or replace wire harness. Do not attempt to stretch harnesses that are too short, since mechanical strain can result in wire breakage.

ABS Component Connector Wire Terminal

Controller Harness

17‑Way AMP

MCP 2.8 (X1)

1718091‑1

927768‑9 1 ‑ 2.5 mm X1‑12 & 18

Controller Harness

18‑Way AMP

MCP 2.8 (X2)

8‑968974‑1

968874

2.5 ‑ 4 mm

Controller Harness

15‑Way AMP

MCP 2.8 (X3)

8‑968973‑1

968873

1.0 ‑ 2.5 mm

ABS Modulator

Harness

AMP Twist‑Lock

(Bayonet)

1‑967325‑2

Wire Seal/

Plug

N/A

N/A N/A

Terminal

Lock

967634

Terminal Crimp Tool

539723‑2

ATC Modulator

Harness

929975‑1

AMP Twist‑Lock

(Bayonet)

1‑967325‑3

ABS Modulator

Harness

3‑pin Packard

Metri‑Pack 280 Series

12040977

12077411

12015323

WS-24™ Wheel Speed Sensor Connectors

Deutsch DTM06

series

CHART 5 - BENDIX® EC‑80™ CONTROLLER COMPONENT CONNECTORS

Deutsch DT04

series

N/A N/A

12034145

Standard round

two pin

539635‑1

12155975

Speed Sensor

Mounting Block

Troubleshooting: Wiring

(CONTINUED)

Mounting Block

Max. Gap

(Sensor to Exciter)

.015 Inches

WS‑24™ Speed Sensor

(90 Deg.)

100 Tooth (typical)

Speed Sensor Exciter

Ring

Hub Assembly

Brake Drum

WS‑24™ speed sensor

90° Speed

Sensors

Sensor

Clamping

Sleeve

100 Tooth

Exciter

Ring

Straight Speed

Sensors

FIGURE 12 ‑ BENDIX® WS‑24™ WHEEL SPEED SENSOR INSTALLATION

Wheel Speed Sensor Wiring

Route sensor wiring coming out of the wheel ends away from moving brake components. Sensor wiring needs to be secured to the axle to prevent excess cable length and wiring damage. It is required that cable ties be installed to the sensor wire within 3 inches (76.2 mm) of the sensor head to provide strain relief.

Following the axle, the sensor wires must be attached along the length of the service brake hoses using cable ties with ultraviolet protection and secured every 6 to 8 inches

(152 to 203 mm). Sufcient – but not excessive – cable

length must be provided to permit full suspension travel and steering axle movement. Install wires so that they cannot touch rotating elements such as wheels, brake discs or drive shafts. Radiation protection may be necessary in the area of brake discs.

Bendix does not recommend using standard tie‑wraps to secure wiring harnesses directly to rubber air lines. This may cause premature wiring failure from the pressure exerted on the wiring when air pressure is applied through the air line. Non‑metallic hose clamps or bow‑tie tie‑wraps are preferred.

The use of grommets or other suitable protection is required whenever the cable must pass through metallic frame members.

All sensor wiring must utilize twisted pair wire, with approx‑ imately one to two twists per inch.

It is recommended that wires be routed straight out of a connector for a minimum of three inches before the wire is allowed to bend.

WSS_DR+

WSS_DR-

WSS_DL+

WSS_DL-

15 18

30A

PMV_DR_HLD

PMV_DR_REL

PMV_DR_CMN

PMV_DL_HLD

PMV_DL_REL

PMV_DL_CMN

PMV_SR_HLD

PMV_SR_REL

PMV_SR_CMN

PMV_SL_HLD

PMV_SL_REL

PMV_SL_CMN

WSS_SR+

WSS_SR-

WSS_SL+

WSS_SL-

10 13

476

Troubleshooting: Bendix® EC-80™ ABS Wiring Schematic

(4S/4M)

DRIVE AXLE STEER AXLE

NOT USED

J1939_ LO

J1939_ HI

NOT USED

GROUND

IGNITION

TRAILER ABS WL

ABS WL

WL_INTERLOCK

ABS WL GND

NOT USED

* * *

BATTERY

RETARDER

RELAY

+12 VOLT BATTERY

WSS DRIVE

AXLE RIGHT

WSS DRIVE AXLE LEFT

DRIVE AXLE RIGHT PMV

DRIVE AXLE LEFT PMV

ABS INDICATOR LAMP

STEER AXLE RIGHT PMV

STEER AXLE LEFT PMV

WSS STEER AXLE RIGHT

WSS STEER AXLE LEFT

TRAILER ABS

INDICATOR

LAMP

DIAGNOSTIC

SWITCH

+12 VOLT IGNITION

* Pressure Modulator Valves

Connector Twist‑Lock Packard

Common (CMN) Pin 2 Pin B

Hold (HLD) Pin 3 Pin C

Release (REL) Pin 1 Pin A

FIGURE 16 - BENDIX® EC‑80™ ABS WIRING SCHEMATIC (4S/4M)

15 18

30A

10 13

47 6

11 14

7 6

13 9

Troubleshooting: Bendix® EC-80™ ATC Wiring Schematic

(6S/6M)

PMV_AL_REL PMV_AL_CMN

PMV_AL_HLD

PMV_AR_REL PMV_AR_CMN PMV_AR_HLD

WSS_AL‑ WSS_AL+

WSS_AR‑ WSS_AR+

DIFF_CMN DIFF

INPUT/OUTPUT 3

INPUT/OUTPUT 2

ABS ORS

WSS_SL‑ WSS_SL+

WSS_SR‑ WSS_SR+

PMV_SL_REL

PMV_SL_CMN PMV_SL_HLD

PMV_SR_REL PMV_SR_CMN PMV_SR_HLD

PMV_DL_REL PMV_DL_CMN

PMV_DL_HLD

PMV_DR_REL PMV_DR_CMN PMV_DR_HLD

WSS_DL‑ WSS_DL+

WSS_DR‑ WSS_DR+

SLS ABS WL GND WL_INTERLOCK ABS WL

TRAILER ABS WL

IGNITION

GROUND

RETARDER

BATTERY

J1939_HI

J1939_LO

NOT USED NOT USED

TCV_DA_CMN TCV_DA

ATC LAMP/ATCO RS

DIFF

LOCK

* * * * * *

SOL

WSS

STEER

WSS

DRIVE

ADD

AXLE

STEER

DRIVE

AXLE

ADD

AXLE

LEFT

ADD

AXLE

RIGHT

LEFT

RIGHT

LEFT

RIGHT

AXLE

LEFT

PMV

STEER

AXLE

RIGHT

PMV

AXLE

LEFT

PMV

DRIVE

AXLE

RIGHT

PMV

LEFT

RIGHT

VALVE

TRACTION

CONTROL

PMV

(TCV)

ADDITIONAL AXLE

ABS

OFF‑ROAD

SWITCH

(ORS)

* Pressure Modulator Valves

Connector Twist‑Lock Packard

Common (CMN) Pin 2 Pin B

Hold (HLD) Pin 3 Pin C

STEER AXLE

STOP LAMP

ABS INDICATOR

LAMP

(SLS)

DRIVE AXLE

TRAILER ABS

INDICATOR LAMP

RETARDER

(OPTIONAL)

RELAY

ATC

OFF‑ROAD

SWITCH

(ORS)

ATC LAMP

STOP LAMPS WITCH

+12V BATTERY

+12 IGNITION

Release (REL) Pin 1 Pin A

FIGURE 17 - BENDIX® EC‑80™ ABS WIRING SCHEMATIC (6S/6M) 36

Troubleshooting: Bendix® EC-80™ ATC Wiring Schematic

C ORS

(6S/5M)

NOT USED

30A

* * * * *

ADD

AXLE

DIFF

LOCK

21 3

PMV

WS S

ADD

AXLE

LEFT

AXLE

RIGHT

AXLE

RIGHT

STEER

DRIVE

AXLE

LEFT

AXLE

LEFT

RIGHT

LEFT

RIGHT

LEFT

RIGHT

PMV

ADDITIONAL AXLE

DRIVE AXLE STEER AXLE

ABS

(OPTIONAL)

RETARDER

RELAY

OFF-ROAD

SWITCH

(ORS)

ABS INDICA TO R LAMP

TRAILER ABS

DIAGNOSTIC

SWITCH

INDICATOR LAMP

* Pressure Modulator Valves

Connector Twist‑Lock Packard

Common (CMN) Pin 2 Pin B

Hold (HLD) Pin 3 Pin C

Release (REL) Pin 1 Pin A

ST OP LAMP

ST OP LAM PS WITCH

(SLS)

+12VBAT TERY

+12 IGNITION

WS S

ADD

SOL

WSS

STEER

WS S

STEER

WS S

DRIVE

WS S

DRIVE

PMV_AA_REL

PMV_AA_CMN

PMV_AA_HLD

WSS_ALWSS_AL+

11 14

WSS_AR-

WSS_AR+

DIFF_CM N DIFF

INPUT/OUTPUT 3

INPUT/OUTPUT 2

ABS ORS

WSS_SL-

WSS_SL+

WSS_SR-

WSS_SR+

PMV_SL_REL

PMV_SL_CMN

PMV_SL_HLD

PMV_SR_REL PMV_SR_CMN PMV_SR_HLD

47 6

PMV_DL_REL

PMV_DL_CMN

PMV_DL_HLD

PMV_DR_REL PMV_DR_CM N

PMV_DR_HLD

10 13

WSS_DLWSS_DL+

15 18

WSS_DR-

WSS_DR+

SLS

ABS WL GND

WL_INTERLOCK

ABS WL

TRAILER ABS WL

IGNITION

GROUND

RET ARDER

BA TTER Y

J1939_HI

J1939_LO

NOT USED

TCV_DA_CM N TCV_DA

AT C LAMP/ AT

VA LV E

(TCV)

TRACTION

CONTROL

ATC

FIGURE 18 - BENDIX® EC‑80™ ATC WIRING SCHEMATIC (6S/5M)

OFF-ROAD

SWITCH

(ORS)

AT C LAM P

NOTES

GLOSSARY

ABS — Antilock Brake System.

ABS Event — Impending wheel lock situation that causes the

ABS controller to activate the modulator valve(s).

ABS Indicator Lamp — An amber lamp which indicates the operating status of an antilock system. When the indicator lamp is on, ABS is disabled and the vehicle reverts to normal brake operation.

Air Gap — Distance between the Sensor and tone ring.

ASR — Automatic Slip Regulation. Another name for traction

control.

ATC — Automatic Traction Control. An additional ABS function in which engine torque is controlled and brakes are applied differentially to enhance vehicle traction.

ATC/ESP Lamp — A lamp that indicates when stability functions, including traction control, roll stability program or yaw control are operating.

Channel — A controlled wheel site.

CAN — Controller Area Network. J1939 is an SAE version of

the CAN link.

Clear Codes — System to erase historical diagnostic trouble codes from the ECU, from either the Diagnostic Switch or from a hand‑held diagnostic tool (only repaired diagnostic trouble codes may be cleared).

Conguration — The primary objective is to identify a “normal” set of sensors and modulators for the Electronic Control Unit, so that it will identify future missing sensors and modulators.

Diagnostic Connector — Diagnostic receptacle in vehicle cab for connection of J1587 hand‑held or PC‑based test equipment. The tester can initiate test sequences, and can also read system parameters.

Diagnostic Switch — A switch used to activate blinks codes.

Differential Braking — Application of brake force to a spinning

wheel so that torque can be applied to wheels which are not slipping.

ECU — Electronic Control Unit.

ESP — Electronic Stability Program. Full stability function that

includes RSP & YC subfunctions.

Diagnostic Trouble Code — A condition that interferes with the generation or transmission of response or control signals in the vehicle's ABS system that could lead to the functionality of the ABS system becoming inoperable in whole or in part.

FMVSS-121 — Federal Motor Vehicle Safety Standard which regulates air brake systems.

HSA — Hill Start Assist. HSA interfaces between the transmission and braking system to help the driver prevent the vehicle from rolling downhill when moving up a steep incline from a stationary position.

IR — Independent Regulation. A control method in which a wheel is controlled at optimum slip, a point where retardation and stability are maximized. The brake pressure that is best for the wheel in question is directed individually into each brake chamber.

J1587 — The SAE heavy‑duty standard diagnostic data link.

J1708 — An SAE standard which denes the hardware and

software protocol for implementing 9600 baud heavy vehicle data links. J1587 version of a J1708 data link.

J1939 — A high speed 250,000 baud data link used for communications between the ABS ECU engine, transmission and retarders.

LAS — Lateral Acceleration Sensor.

MIR — Modied Independent Regulation. A method of controlling

the opposite sides of a steer axle during ABS operation so that torque steer and stopping distance are minimized.

PLC — Power Line Carrier. The serial communication protocol used to communicate with the trailer over the blue full time power wire.

PMV — Pressure Modulator Valve. An air valve which is used to vent or block air to the brake chambers to limit or reduce brake torque.

QR — Quick Release. Quick release valves allow faster release of air from the brake chamber after a brake application. To balance the system, quick release valves have hold off springs that produce higher crack pressures (when the valves open).

Relay Valve — Increases the application speed of the service brake. Installed near brakes with larger air chambers (type 24 or

30). The treadle valve activates the relay valve with an air signal. The relay valve then connects its supply port to its delivery ports. Equal length air hose must connect the delivery ports of the relay valve to the brake chambers.

Retarder Relay — A relay which is used to disable a retarder when ABS is triggered.

RSP — Roll Stability Program. An all‑axle ABS solution that helps reduce vehicle speed by applying all vehicle brakes as needed, reducing the tendency to roll over.

SAS — Steering Angle Sensor.

Sensor Clamping Sleeve — A beryllium copper sleeve which

has ngers cut into it. It is pressed between an ABS sensor and

mounting hole to hold the sensor in place.

Stored Diagnostic Trouble Codes — A diagnostic trouble code that occurred.

TCS — Traction Control System, another name for ATC or ASR.

Tone Ring — A ring that is usually pressed into a wheel hub that

has a series of teeth (usually 100) and provides actuation for the speed sensor. Note maximum run out is .008.

YC — Yaw Control. Helps stabilize rotational dynamics of vehicle.

YRS — Yaw Rate Sensor.

Appendix: J1939 SPN and FMI Codes and their

Bendix Blink Code Equivalents

APPENDIX: J1939 SPN and FMI Codes and their Bendix Blink Code Equivalents

Bendix Blink Code

SPN

(J1939)

154 13 Miscellaneous 12 23 I/O 2 or I/O 3 Shorted High

168 3 Power Supply 6 2 Battery Voltage Too High

168 4 Power Supply 6 1 Battery Voltage Too Low

564 3 Miscellaneous 12 13 Diff Lock Solenoid Shorted to Voltage

564 4 Miscellaneous 12 12 Diff Lock Solenoid Shorted to Ground or Open Circuit

575 14 Miscellaneous 12 17 ABS Disabled Due to Off-Road Mode

576 14 Miscellaneous 12 3 ATC Disabled or Dynamometer Test Mode Active

612 14 Miscellaneous 12 21 ABS Disabled Due to Engaged Differential Lock

614 3 Miscellaneous 12 23 IO3 Solenoid Shorted to Voltage

615 14 Miscellaneous 12 19 Maximum Number of PMV Cycles Exceeded

615 14 Miscellaneous 12 20 Maximum Number of TCV Cycles Exceeded

629 2 ECU 13 4 ECU (2678C)

629 2 ECU 13 5 ECU (1C)

629 2 ECU 13 7 Conﬁguration Mismatch

629 2 ECU 13 17 ECU (C8C)

629 8 Miscellaneous 12 29 Air System/Mechanical Component

629 12 ECU 13 3 ECU (10)

629 12 ECU 13 14 ECU (C6)

629 12 ECU 13 15 ECU (CF)

629 12 ECU 13 16 ECU (C0)

629 14 Miscellaneous 12 28 Air System/Mechanical Component

629 14 ECU 13 1 ECU (5F3)

630 12 ECU 13 6 ECU (6CD)

630 12 ECU 13 19 ECU (63)

630 12 ECU 13 20 ECU (6E)

630 12 ECU 13 10 ECU (5FC)

630 13 ECU 13 13 Conﬁguration Mismatch

630 13 ECU 13 2 ECU (5CD)

630 13 ECU 13 8 ECU (56)

630 13 ECU 13 9 ECU (CA3C)

630 13 ECU 13 18 ECU (CC)

630 13 ECU 13 21 ECU (6C)

630 13 ECU 13 22 ECU (63C)

630 13 ECU 13 25 VIN Mismatch

630 13 ECU 13 26 Valve Conﬁguration Mismatch

639 2 J1939 11 3 J1939 Engine (EEC1) Electronic Engine Controller Loss of Communication or Time Out

639 2 J1939 11 2 J1939 Electronic Retarder Timeout or Invalid Signal (ERC1)

639 2 J1939 11 4 J1939 Electronic Engine Controller 2 Timeout or Invalid Message (EEC2)

639 2 J1939 11 7 Timeout or Invalid Data on ETC7 or VP15 Transmission Message for HSA

639 2 J1939 11 8 Timeout or Invalid Data on XBR Message

FMI

(J1939)

General

Equivalent(s)

(1st

Digit)

(2nd

Diagnostic Trouble Code Description

Digit)

APPENDIX: J1939 SPN and FMI Codes and their Bendix Blink Code Equivalents

Bendix Blink Code

SPN

(J1939)

639 2 J1939 11 10

639 2 J1939 11 11 AUXIO CAN Message Timeout

639 2 J1939 11 12 J1939 Hill Start Aid Switch Signal Not Available

639 2 J1939 11 15 J1939 Engine (EEC3) Electronic Transmission Controller loss of communications or time out

639 2 J1939 11 16

639 2 J1939 11 3

639 2 J1939 11 2 J1939 Retarder (ERC1) Electronic Retarder Controller loss of communications or time out

639 2 J1939 11 4 J1939 Engine (EEC2) Electronic Engine Controller loss of communications or time out

639 2 J1939 11 10 J1939 Transmission Loss of Communications, ETC1 message

639 2 J1939 11 15 J1939 Engine Loss of Communications, EEC2 message

639 2 J1939 11 16 J1939 Transmission Loss of Communications, ETC2 message

639 12 J1939 11 1 J1939 Serial Link Loss of Communication Between EC-80 ECU and Other Devices

789 1 Wheel Speed Sensor 2 1 SA Left WSS Excessive Air Gap

789 2 Wheel Speed Sensor 2 3 SA Left WSS Open or Shorted

789 7 Wheel Speed Sensor 2 5 SA Left WSS Wheel End

789 8 Wheel Speed Sensor 2 6 SA Left WSS Erratic Sensor Signal

789 9 Wheel Speed Sensor 2 2 SA Left WSS Output Low @ Drive-Off

789 10 Wheel Speed Sensor 2 4 SA Left WSS Loss of Sensor Signal

789 13 Wheel Speed Sensor 2 7 SA Left WSS Tire Size Calibration

790 1 Wheel Speed Sensor 3 1 SA Right WSS Excessive Air Gap

790 2 Wheel Speed Sensor 3 3 SA Right WSS Open or Shorted

790 7 Wheel Speed Sensor 3 5 SA Right WSS Wheel End

790 8 Wheel Speed Sensor 3 6 SA Right WSS Erratic Sensor Signal

790 9 Wheel Speed Sensor 3 2 SA Right WSS Output Low @ Drive-Off

790 10 Wheel Speed Sensor 3 4 SA Right WSS Loss of Sensor Signal

790 13 Wheel Speed Sensor 3 7 SA Right WSS Tire Size Calibration

791 1 Wheel Speed Sensor 4 1 DA Left WSS Excessive Air Gap

791 2 Wheel Speed Sensor 4 3 DA Left WSS Open or Shorted

791 7 Wheel Speed Sensor 4 5 DA Left WSS Wheel End

791 8 Wheel Speed Sensor 4 6 DA Left WSS Erratic Sensor Signal

791 9 Wheel Speed Sensor 4 2 DA Left WSS Output Low @ Drive-Off

791 10 Wheel Speed Sensor 4 4 DA Left WSS Loss of Sensor Signal

791 13 Wheel Speed Sensor 4 7 DA Left WSS Tire Size Calibration

792 1 Wheel Speed Sensor 5 1 DA Right WSS Excessive Air Gap

792 2 Wheel Speed Sensor 5 3 DA Right WSS Open or Shorted

792 7 Wheel Speed Sensor 5 5 DA Right WSS Wheel End

792 8 Wheel Speed Sensor 5 6 DA Right WSS Erratic Sensor Signal

792 9 Wheel Speed Sensor 5 2 DA Right WSS Output Low @ Drive-Off

792 10 Wheel Speed Sensor 5 4 DA Right WSS Loss of Sensor Signal

792 13 Wheel Speed Sensor 5 7 DA Right WSS Tire Size Calibration

793 1 Wheel Speed Sensor 14 1 AA Left WSS Excessive Air Gap

FMI

(J1939)

General

Equivalent(s)

(1st

Digit)

(2nd

Diagnostic Trouble Code Description

Digit)

J1939 Transmission (ETC1) Electronic Transmission Controller, loss of communication message or time out

J1939 Transmission (ETC2) Electronic Transmission Controller loss of communications or time out

J1939 Engine (EEC1) Electronic Engine Controller loss of communications between EC-80 ECU and other devices

APPENDIX: J1939 SPN and FMI Codes and their Bendix Blink Code Equivalents

Bendix Blink Code

SPN

(J1939)

793 2 Wheel Speed Sensor 14 3 AA Left WSS Open or Shorted

793 7 Wheel Speed Sensor 14 5 AA Left WSS Wheel End

793 8 Wheel Speed Sensor 14 6 AA Left WSS Erratic Sensor Signal

793 9 Wheel Speed Sensor 14 2 AA Left WSS Output Low @ Drive-Off

793 10 Wheel Speed Sensor 14 4 AA Left WSS Loss of Sensor Signal

794 1 Wheel Speed Sensor 15 1 AA Right WSS Excessive Air Gap

794 2 Wheel Speed Sensor 15 3 AA Right WSS Open or Shorted

794 7 Wheel Speed Sensor 15 5 AA Right WSS Wheel End

794 8 Wheel Speed Sensor 15 6 AA Right WSS Erratic Sensor Signal

794 10 Wheel Speed Sensor 15 4 AA Right WSS Loss of Sensor Signal

794 14 Wheel Speed Sensor 15 2 AA Right WSS Output Low @ Drive-Off

795 5 Pressure Modulator Valve 7 7 SA Left PMV CMN Open Circuit

795 13 Pressure Modulator Valve 7 8 SA Left PMV Conﬁguration Error

796 5 Pressure Modulator Valve 8 7 SA Right PMV CMN Open Circuit

796 13 Pressure Modulator Valve 8 8 SA Right PMV Conﬁguration Error

797 5 Pressure Modulator Valve 9 7 DA Left PMV CMN Open Circuit

797 13 Pressure Modulator Valve 9 8 DA Left PMV Conﬁguration Error

798 5 Pressure Modulator Valve 10 7 DA Right PMV CMN Open Circuit

798 13 Pressure Modulator Valve 10 8 DA Right PMV Conﬁguration Error

799 5 Pressure Modulator Valve 16 7 AA Left PMV CMN Open Circuit

799 13 Pressure Modulator Valve 16 8 AA Left PMV Conﬁguration Error

800 5 Pressure Modulator Valve 17 7 AA Right PMV CMN Open Circuit

800 13 Pressure Modulator Valve 17 8 AA Right PMV Conﬁguration Error

801 2 Miscellaneous 12 4 Retarder Relay Open Circuit or Shorted to Ground

801 3 Miscellaneous 12 5 Retarder Relay Circuit Shorted to Voltage

802 3 Miscellaneous 12 8 PMV/TCV/Diff Lock Common Shorted to Voltage

802 4 Miscellaneous 12 7 PMV/TCV/Diff Lock Common Shorted to Ground

802 12 ECU 13 11 ECU (F1A)

802 12 ECU 13 12 ECU (F14)

805 14 Miscellaneous 12 9 ATC Disabled to Prevent Brake Fade

806 3 TCV 18 2 TCV Solenoid Shorted to Voltage

806 4 TCV 18 1 TCV Solenoid Shorted to Ground

806 5 TCV 18 3 TCV Solenoid Open Circuit

806 13 TCV 18 4 TCV Conﬁguration Error

810 7 Miscellaneous 12 11 Wheel Speed Sensors Reversed on an Axle

811 2 Miscellaneous 12 6 ABS Warning Lamp Circuit

815 13 Wheel Speed Sensor 14 10 Additional Axle WSS Conﬁguration Error

932 3 Pressure Modulator Valve 7 5 SA Left PMV HLD Solenoid Shorted to Voltage

932 4 Pressure Modulator Valve 7 4 SA Left PMV HLD Solenoid Shorted to Ground

932 5 Pressure Modulator Valve 7 6 SA Left PMV HLD Solenoid Open Circuit

933 3 Pressure Modulator Valve 8 5 SA Right PMV HLD Solenoid Shorted to Voltage

933 4 Pressure Modulator Valve 8 4 SA Right PMV HLD Solenoid Shorted to Ground

933 5 Pressure Modulator Valve 8 6 SA Right PMV HLD Solenoid Open Circuit

FMI

(J1939)

General

Equivalent(s)

(1st

Digit)

(2nd

Diagnostic Trouble Code Description

Digit)

APPENDIX: J1939 SPN and FMI Codes and their Bendix Blink Code Equivalents

Bendix Blink Code

SPN

(J1939)

934 3 Pressure Modulator Valve 9 5 DA Left PMV HLD Solenoid Shorted to Voltage

934 4 Pressure Modulator Valve 9 4 DA Left PMV HLD Solenoid Shorted to Ground

934 5 Pressure Modulator Valve 9 6 DA Left PMV HLD Solenoid Open Circuit

935 3 Pressure Modulator Valve 10 5 DA Right PMV HLD Solenoid Shorted to Voltage

935 4 Pressure Modulator Valve 10 4 DA Right PMV HLD Solenoid Shorted to Ground

935 5 Pressure Modulator Valve 10 6 DA Right PMV HLD Solenoid Open Circuit

936 3 Pressure Modulator Valve 16 5 AA Left PMV HLD Solenoid Shorted to Voltage

936 4 Pressure Modulator Valve 16 4 AA Left PMV HLD Solenoid Shorted to Ground

936 5 Pressure Modulator Valve 16 6 AA Left PMV HLD Solenoid Open Circuit

937 3 Pressure Modulator Valve 17 5 AA Right PMV HLD Solenoid Shorted to Voltage

937 4 Pressure Modulator Valve 17 4 AA Right PMV HLD Solenoid Shorted to Ground

937 5 Pressure Modulator Valve 17 6 AA Right PMV HLD Solenoid Open Circuit

938 3 Pressure Modulator Valve 7 2 SA Left PMV REL Solenoid Shorted to Voltage

938 4 Pressure Modulator Valve 7 1 SA Left PMV REL Solenoid Shorted to Ground

938 5 Pressure Modulator Valve 7 3 SA Left PMV REL Solenoid Open Circuit

939 3 Pressure Modulator Valve 8 2 SA Right PMV REL Solenoid Shorted to Voltage

939 4 Pressure Modulator Valve 8 1 SA Right PMV REL Solenoid Shorted to Ground

939 5 Pressure Modulator Valve 8 3 SA Right PMV REL Solenoid Open Circuit

940 3 Pressure Modulator Valve 9 2 DA Left PMV REL Solenoid Shorted to Voltage

940 4 Pressure Modulator Valve 9 1 DA Left PMV REL Solenoid Shorted to Ground

940 5 Pressure Modulator Valve 9 3 DA Left PMV REL Solenoid Open Circuit

941 3 Pressure Modulator Valve 10 2 DA Right PMV REL Solenoid Shorted to Voltage

941 4 Pressure Modulator Valve 10 1 DA Right PMV REL Solenoid Shorted to Ground

941 5 Pressure Modulator Valve 10 3 DA Right PMV REL Solenoid Open Circuit

942 3 Pressure Modulator Valve 16 2 AA Left PMV REL Solenoid Shorted to Voltage

942 4 Pressure Modulator Valve 16 1 AA Left PMV REL Solenoid Shorted to Ground

942 5 Pressure Modulator Valve 16 3 AA Left PMV REL Solenoid Open Circuit

943 3 Pressure Modulator Valve 17 2 AA Right PMV REL Solenoid Shorted to Voltage

943 4 Pressure Modulator Valve 17 1 AA Right PMV REL Solenoid Shorted to Ground

943 5 Pressure Modulator Valve 17 3 AA Right PMV REL Solenoid Open Circuit

1045 2 Miscellaneous 12 2 Stop Lamp Switch Defective

1045 7 Miscellaneous 12 1 Stop Lamp Switch Not Detected

2622 2 Miscellaneous 12 24 HSA Lamp Open Circuit or Shorted to Ground

2622 3 Miscellaneous 12 26 HSA Valve Solenoid Shorted to Voltage

2622 3 Miscellaneous 12 31 HSA Lamp Shorted to Voltage

2622 4 Miscellaneous 12 25 HSA Valve Solenoid Shorted to Ground

2622 5 Miscellaneous 12 33 HSA Valve Solenoid Open Circuit

FMI

(J1939)

General

Equivalent(s)

(1st

Digit)

(2nd

Diagnostic Trouble Code Description

Digit)

Bendix Commercial Vehicle Systems EC-80 User Manual

Specifications and Main Features

Frequently Asked Questions

User Manual