Dodge RAM 1995 User Manual

dodge :: Dodge Truck RAM 2500 Van V6-239 3.9L
Magnum (1995)

> Relays and Modules > Relays and Modules - Brakes and Traction Control > ABS Light Relay > Component Information > Locations

ABS Light Relay: Locations

Warning Lamp Relay

The ABS Light Relay is located behind the dash on the right side of the steering column.

> Relays and Modules > Relays and Modules - Brakes and Traction Control > ABS Light Relay > Component Information > Locations > Page 7

Warning Lamp Relay

> Relays and Modules > Relays and Modules - Brakes and Traction Control > ABS Main Relay > Component Information > Locations

Related Images

> Relays and Modules > Relays and Modules - Brakes and Traction Control > ABS Main Relay > Component Information > Locations > Page 11

Related Images

> Relays and Modules > Relays and Modules - Brakes and Traction Control > ABS Main Relay > Component Information > Locations > Page 12

ABS Main Relay: Description and Operation

(ABS)

(PDC)

When the Anti-Lock Brake System control module grounds the ABS power relay on circuit B116, the relay contacts close connecting circuit A10from the Power Distribution Center and circuit B120. Circuit A1O connects to fuse 4 in the PDC. Circuit A2O from fuse 5 in the fuse blocksplices to feed the coil side of the ABS power relay.

From the ABS power relay, circuit B120 splices to supply voltage to the ABS pump motor and all the solenoids in the front brake anti-lock valve. CircuitB120 also supplies power to the solenoids in the rear anti-lock valve. Additionally, circuit B120 provides an input to cavity 34 of the ABS controlmodule. The input tells the ABS control module that voltage has been supplied to the pump motor.

> Relays and Modules > Relays and Modules - Brakes and Traction Control > Electronic Brake Control Module > Component Information > Locations

Related Images

> Relays and Modules > Relays and Modules - Brakes and Traction Control > Electronic Brake Control Module > Component Information > Diagrams > 2-Way Connector

Related Images

> Relays and Modules > Relays and Modules - Brakes and Traction Control > Electronic Brake Control Module > Component Information > Diagrams > 2-Way Connector > Page 18

Related Images

> Relays and Modules > Relays and Modules - Brakes and Traction Control > Electronic Brake Control Module > Component Information > Description and Operation > With Four Wheel Antilock Brakes

Electronic Brake Control Module: Description and OperationWith Four Wheel Antilock Brakes
PURPOSE

(CAB)

The Controller - Antilock Brake is mounted under the hood, separately from the valve body, and has microprocessor circuits that:-

Monitor the brake switch input to tell whether or not to prepare for possible antilock braking.

- Monitor the wheel speed sensor inputs to determine when a wheel is tending to lock up.

­Operate the integral control unit assembly during antilock braking based on comparing the speed sensors to information programmed inmemory.

- Detect ABS system related problems and take diagnostic action.

OPERATION

The CAB will disable antilock control and set a soft ignition latched trouble code if it detects one of the following conditions with itself:-

(71) RAM Read/Write

- (72) ROM Checksum

- (73) Watchdog

> Relays and Modules > Relays and Modules - Brakes and Traction Control > Electronic Brake Control Module > Component Information > Description and Operation > With Four Wheel Antilock Brakes > Page 21

Electronic Brake Control Module: Description and OperationWith Rear Wheel Antilock Brakes

Anti-Lock Electronic Control Module

PURPOSE

All phases of anti-lock mode brake operation are monitored and controlled by the Controller Antilock Brake module (CAB).

OPERATION

The module operates independently from other electrical circuits in the vehicle.
CAB input/output circuits include the system hydraulic valve, indicator lamps, and the speed sensor.

Speed sensor inputs are continuously monitored and interpreted by the module. The module determines wheel speed and rate of deceleration fromthese inputs and activates the appropriate solenoid in the hydraulic valve when necessary.

The module performs system diagnostic checks and contains a self test program. -

The program is activated when the ignition switch is turned to the ON position.

- In this mode, the module checks indicator light operation, the system electrical circuits and the pressure limiting valve solenoids.

The brake warning and anti-lock indicator lamps are illuminated for approximately two seconds during the system self test cycle.

> Relays and Modules > Relays and Modules - Brakes and Traction Control > Electronic Brake Control Module > Component Information > Service and Repair > With Four Wheel Antilock System

Electronic Brake Control Module: Service and RepairWith Four Wheel Antilock System

Fig. 25 Main Harness Connector

The ABS module is located in the engine compartment attached to the forward side of the front brake anti-lock valve.NOTE:

1. Disconnect upper harness connector from module.2. Lift connector locking handle to release main harness connector for module. Rotate handle upward to clear connector.3. Lift connector up and out of retaining lugs on module.4. Remove module mounting screws then the module.5. Reverse procedure to install, installing harness main connector as follows:

a. Connecting main harness connector to module.b. Seat connector in module retaining lugs and start connector into module.c. Rotate connector locking handle downward into position to seat and retain connector.

> Relays and Modules > Relays and Modules - Brakes and Traction Control > Electronic Brake Control Module > Component Information > Service and Repair > With Four Wheel Antilock System > Page 24

Electronic Brake Control Module: Service and RepairWith Rear Wheel Antilock System

On models with A/C,

1. Disconnect battery ground cable.2. remove glove compartment.3. remove module attaching screws from righthand side of dash panel.On all models,

Fig. 98 CAB Module Replacement

4. Disconnect electrical connector from module, then remove the module.5. Reverse procedure to install. attaching screws to inch lbs.Torque 21

> Relays and Modules > Relays and Modules - Instrument Panel > ABS Light Relay > Component Information > Locations

ABS Light Relay: Locations

Warning Lamp Relay

The ABS Light Relay is located behind the dash on the right side of the steering column.

> Relays and Modules > Relays and Modules - Instrument Panel > ABS Light Relay > Component Information > Locations > Page 29

Warning Lamp Relay

> Relays and Modules > Relays and Modules - Instrument Panel > Key Reminder Relay > Component Information > Locations

Key Reminder Relay: Locations

Fuse Block (Part 1 Of 2)

> Relays and Modules > Relays and Modules - Instrument Panel > Key Reminder Relay > Component Information > Locations > Page 33

RAM 2500 Van V6-239 3.9L Magnum (1995)

Fuse Block (Part 2 Of 2)

> Relays and Modules > Relays and Modules - Instrument Panel > Key Reminder Relay > Component Information > Locations > Page 34

Key Reminder Relay: Description and Operation

The time delay relay is used to allow a time-ON function for the ignition switch lamp and the headlamp switch lamp. Power for the relay is provided onthe M11 circuit from the interior lamp defeat switch.

Circuit M2 provides ground for the time delay relay through the door ajar switches, headlamp switch and the power door lock module. When a door isopened, or the headlamp switch is moved to the dome lamp position, a ground path is provided for the relay on circuit M2. This energizes the relay,causing the contacts to close.

When the relay contacts close, power is provided through the relay to circuit M50. The M50 circuit supplies current to the ignition switch lamp and theheadlamp switch lamp. Circuit Z1 provides ground for the lamps. Circuit Z1 terminates at the instrument panel, above the headlamp switch. Circuit Z1also provides ground for the ash receiver lamp, cigar lighter lamp, and glove box lamp.

> Relays and Modules > Relays and Modules - Lighting and Horns > Daytime Running Lamp Control Unit > Component Information > Description and Operation

Daytime Running Lamp Control Unit: Description and Operation

CANADIAN VEHICLES

On Canadian vehicles, the low-beam headlamps operate when the ignition switch is in the RUN position and the headlamp switch is OFF.

when the ignition switch is in the RUN position, circuit A1 from fuse 7 in the Power Distribution Center (PDC) connects to circuit A21. Circuit A21supplies voltage to the DRL module.
Circuit L2O from the headlamp switch connects to the DRL module. Circuit L2O is HOT at all times.

The DRL module receives the vehicle speed sensor input from circuit G7. Circuit G34 from the DRL module provides power for the high beam indicatorlamp in the instrument cluster.

Circuit L4 powers the low-beams of the left and right headlamps. When the headlamp switch is OFF, the DRL module powers the low beams on circuitL4. When the headlamps are ON, the multi-function switch powers the low beams on circuit L4.

Circuit L3 feeds the high beams of the headlamps. When the operator flashes the headlamps with the stalk of the multi-function switch, the DRL sensesvoltage on circuit L3. When it senses voltage on circuit L3, the DRL module stops supplying power to the low beams on circuit L4.
Circuit Z1 provides ground for the DRL module. Circuit Z1 terminates at the left side of the dash panel.

> Relays and Modules > Relays and Modules - Powertrain Management > Relays and Modules - Computers and Control Systems > Powertrain Control Module <--> [Engine Control Module] > Component Information >

Technical Service Bulletins > Customer Interest for Powertrain Control Module: > 182395 > Jun > 95 > PCM - Cold Start Sag/Hesitation or Backfire/Pop

Powertrain Control Module: Customer InterestPCM - Cold Start Sag/Hesitation or Backfire/Pop

NO: 18-23-95
GROUP: Vehicle Performance
DATE: Jun. 30, 1995

SUBJECT: Cold Start Sag/Hesitation and/or Exhaust Backfire or Pop

MODELS: 1994 - 1995

(AB) Ram Van/Wagon
1994 - 1995 (AN) Dakota
1994 - 1995 (BR) Ram Truck

:NOTE

THIS BULLETIN APPLIES TO VEHICLES EQUIPPED WITH A 3.9L ENGINE.

SYMPTOM/CONDITION:^

Driving away after a cold start up, a sag/hesitation may be experienced. At idle, a slight engine surge/rough idle may also be felt. The condition maypersist for up to one minute and be most prevalent on cold starts at ambient of 60-80 degrees F.

^

An exhaust backfire or popping noise in the exhaust system may occur during a closed throttle deceleration before the engine has reached normaloperating temperatures.

^ The vehicle may exhibit one or both of these conditions.

DIAGNOSIS:Using the Mopar Diagnostic System (MDS) or Scan Tool (DRB III) with the appropriate Diagnostic Procedure Manual, verify that allengine/transmission systems are functioning as designed. If Diagnostic Trouble Codes (DTC's) are present, record them on the repair order and repairbefore proceeding with the repair procedure in this bulletin.

COLD START SAG/HESITATION:1.

Allow engine to cool down at least eight (8) hours, preferably overnight.

2.

Following cold start drive away, make frequent stops and medium accelerations checking for sags and hesitations. If sags or hesitations result,perform the repair procedure.

While vehicle is still cold, start engine and accelerate in first gear until engine speed reaches 3000 RPM.

2. Remove foot from accelerator pedal. Decelerate the vehicle and allow the vehicle to come to a stop.

3. If a backfire or popping sound comes from the exhaust system during deceleration, perform the repair procedure.

PARTS REQUIRED:1

4798341 POM, 3.9L Man. Trans AN Body 1994 MY
1 4798342 POM, 3.9L Auto Trans. AN Body 1994 MY
1 4798343 POM, 3.9L Auto Trans. AB Body 1994 MY
1 4798344 POM, 3.9L Man. Trans. BR Body 1994 MY
1 4798345 PCM, 3.9L Auto Trans. BR Body 1994 MY
1 4275086 Label - Authorized Modification
1 4669020 Label - Authorized Software Update

> Relays and Modules > Relays and Modules - Powertrain Management > Relays and Modules - Computers and Control Systems > Powertrain Control Module <--> [Engine

Control Module] > Component Information > Technical Service Bulletins > Customer Interest for Powertrain Control Module: > 182395 > Jun > 95 > PCM - Cold Start Sag/

Hesitation or Backfire/Pop > Page 49

RAM 2500 Van V6-239 3.9L Magnum (1995)

EXHAUST BACKFIRE OR POPPING NOISE:1.

EQUIPMENT NEEDED:1

CH6OOO Scan Tool (DRB III)
1 CH7035 General Purpose Interface Bus Cable (GPIB)
1 CH7015 Engine Cable

REPAIR PROCEDURE:

This bulletin includes the replacement of the Powertrain Control Module (PCM) for 1994 model year vehicles, and the flashing of 1995 model yearvehicles with revised software.

MODULE REPLACEMENT:This section of the bulletin involves the replacement of the powertrain control module with one of the above powertrain control modules.

1. Record all radio station presets.

2. Disconnect negative cable at battery and isolate.

3. Remove 60 way electrical connector from POM (one bolt). POM is located in the right rear side of the engine compartment.

4. Remove the three PCM mounting bolts and remove PCM.

5. Install new PCM and torque bolts to 9 in. lbs. (1 Nm) torque.

6. Connect 60 way electrical connector to POM. Torque bolt to 35 in. lbs. (4 Nm).

7. Connect negative cable to battery.

8. Program radio station presets and clock.

9. Proceed to module reprogramming.

1995 MODULE REPROGRAMMING:This section of the bulletin involves reprogramming the PCM with new software and installation of appropriate labels.

: NOTE

THE MOPAR DIAGNOSTIC SYSTEM IS REQUIRED TO PERFORM THE FOLLOWING REPAIR. THE SYSTEM MUST BE OPERATINGWITH RELEASE 16 OR LATER INSTALLED. (TIL CD 1083 OR LATER)

This repair involves selectively erasing and reprogramming the Powertrain Control Module with new software (calibration change).

1. Connect the MDS (Mopar Diagnostic System) and DRBIII (Scan Tool) to the vehicle and power them up.

2. Use the arrow keys and select # 2 MDS DIAGNOSTICS on the DRBIII MAIN MENU Screen.

3. Use the arrow keys and select DIAGNOSTIC MENU on the MDS, then press NEXT MENU.

4. Use the arrow keys and select CONTROLLER PROGRAMMING on the MDS, then press NEXT MENU.

5. Use the arrow keys and select PROGRAM CONTROLLER PART on the MDS, then press NEXT MENU.

6. Follow the steps presented on the MDS and DRBIII which will allow the DRBIII to obtain the current part number of the controller.

7.

The MDS will display the part number of the controller on the vehicle and the appropriate replacement part number, then press NEXT MENU tobegin programming.

If the controller on the vehicle has already been updated or programmed, a NO UPDATES AVAILABLE message will be displayed. Check the partnumber of the controller on the vehicle and compare it to the part number displayed. If the part numbers match and the controller update has beenverified, proceed to Step 9.

8. The MDS and DRBIII will prompt for any operator action needed during the remainder of the programming process.

: NOTE

THE FOLLOWING STEPS ARE REQUIRED BY LAW.

Chrysler Authorized Software Update Label

9.

Type the necessary information on the "Authorized Software Update Label" and attach it to the PCM and cover the label with a clear plasticsticker.

> Relays and Modules > Relays and Modules - Powertrain Management > Relays and Modules - Computers and Control Systems > Powertrain Control Module <--> [Engine

Control Module] > Component Information > Technical Service Bulletins > Customer Interest for Powertrain Control Module: > 182395 > Jun > 95 > PCM - Cold Start Sag/

Hesitation or Backfire/Pop > Page 50

RAM 2500 Van V6-239 3.9L Magnum (1995)

Chrysler Authorized Modification Label

10. Type the necessary information on the Authorized Modification Label and attach the label near the VECI Label.

POLICY: Reimbursable within the provisions of the warranty.
TIME ALLOWANCE: Module. Powertrain Control Reprogram

Labor Operation No: 08-19-42-97 (1995 BR) 0.5 Hrs.

Replace Module. Powertrain Control and Reprogram 08-19-42-98 (1994 BR)

0.7 Hrs.

FAILURE CODE: FM - Flash Module

> Relays and Modules > Relays and Modules - Powertrain Management > Relays and Modules - Computers and Control Systems > Powertrain Control Module <--> [Engine Control Module] > Component Information >

Technical Service Bulletins > All Technical Service Bulletins for Powertrain Control Module: > 182395 > Jun > 95 > PCM - Cold Start Sag/Hesitation or Backfire/Pop

Powertrain Control Module: All Technical Service BulletinsPCM - Cold Start Sag/Hesitation or Backfire/Pop

NO: 18-23-95
GROUP: Vehicle Performance
DATE: Jun. 30, 1995

SUBJECT: Cold Start Sag/Hesitation and/or Exhaust Backfire or Pop

MODELS: 1994 - 1995

(AB) Ram Van/Wagon
1994 - 1995 (AN) Dakota
1994 - 1995 (BR) Ram Truck

:NOTE

THIS BULLETIN APPLIES TO VEHICLES EQUIPPED WITH A 3.9L ENGINE.

SYMPTOM/CONDITION:^

Driving away after a cold start up, a sag/hesitation may be experienced. At idle, a slight engine surge/rough idle may also be felt. The condition maypersist for up to one minute and be most prevalent on cold starts at ambient of 60-80 degrees F.

^

An exhaust backfire or popping noise in the exhaust system may occur during a closed throttle deceleration before the engine has reached normaloperating temperatures.

^ The vehicle may exhibit one or both of these conditions.

DIAGNOSIS:Using the Mopar Diagnostic System (MDS) or Scan Tool (DRB III) with the appropriate Diagnostic Procedure Manual, verify that allengine/transmission systems are functioning as designed. If Diagnostic Trouble Codes (DTC's) are present, record them on the repair order and repairbefore proceeding with the repair procedure in this bulletin.

COLD START SAG/HESITATION:1.

Allow engine to cool down at least eight (8) hours, preferably overnight.

2.

Following cold start drive away, make frequent stops and medium accelerations checking for sags and hesitations. If sags or hesitations result,perform the repair procedure.

While vehicle is still cold, start engine and accelerate in first gear until engine speed reaches 3000 RPM.

2. Remove foot from accelerator pedal. Decelerate the vehicle and allow the vehicle to come to a stop.

3. If a backfire or popping sound comes from the exhaust system during deceleration, perform the repair procedure.

PARTS REQUIRED:1

4798341 POM, 3.9L Man. Trans AN Body 1994 MY
1 4798342 POM, 3.9L Auto Trans. AN Body 1994 MY
1 4798343 POM, 3.9L Auto Trans. AB Body 1994 MY
1 4798344 POM, 3.9L Man. Trans. BR Body 1994 MY
1 4798345 PCM, 3.9L Auto Trans. BR Body 1994 MY
1 4275086 Label - Authorized Modification
1 4669020 Label - Authorized Software Update

> Relays and Modules > Relays and Modules - Powertrain Management > Relays and Modules - Computers and Control Systems > Powertrain Control Module <--> [Engine

Control Module] > Component Information > Technical Service Bulletins > All Technical Service Bulletins for Powertrain Control Module: > 182395 > Jun > 95 > PCM -

Cold Start Sag/Hesitation or Backfire/Pop > Page 56

RAM 2500 Van V6-239 3.9L Magnum (1995)

EXHAUST BACKFIRE OR POPPING NOISE:1.

EQUIPMENT NEEDED:1

CH6OOO Scan Tool (DRB III)
1 CH7035 General Purpose Interface Bus Cable (GPIB)
1 CH7015 Engine Cable

REPAIR PROCEDURE:

This bulletin includes the replacement of the Powertrain Control Module (PCM) for 1994 model year vehicles, and the flashing of 1995 model yearvehicles with revised software.

MODULE REPLACEMENT:This section of the bulletin involves the replacement of the powertrain control module with one of the above powertrain control modules.

1. Record all radio station presets.

2. Disconnect negative cable at battery and isolate.

3. Remove 60 way electrical connector from POM (one bolt). POM is located in the right rear side of the engine compartment.

4. Remove the three PCM mounting bolts and remove PCM.

5. Install new PCM and torque bolts to 9 in. lbs. (1 Nm) torque.

6. Connect 60 way electrical connector to POM. Torque bolt to 35 in. lbs. (4 Nm).

7. Connect negative cable to battery.

8. Program radio station presets and clock.

9. Proceed to module reprogramming.

1995 MODULE REPROGRAMMING:This section of the bulletin involves reprogramming the PCM with new software and installation of appropriate labels.

: NOTE

THE MOPAR DIAGNOSTIC SYSTEM IS REQUIRED TO PERFORM THE FOLLOWING REPAIR. THE SYSTEM MUST BE OPERATINGWITH RELEASE 16 OR LATER INSTALLED. (TIL CD 1083 OR LATER)

This repair involves selectively erasing and reprogramming the Powertrain Control Module with new software (calibration change).

1. Connect the MDS (Mopar Diagnostic System) and DRBIII (Scan Tool) to the vehicle and power them up.

2. Use the arrow keys and select # 2 MDS DIAGNOSTICS on the DRBIII MAIN MENU Screen.

3. Use the arrow keys and select DIAGNOSTIC MENU on the MDS, then press NEXT MENU.

4. Use the arrow keys and select CONTROLLER PROGRAMMING on the MDS, then press NEXT MENU.

5. Use the arrow keys and select PROGRAM CONTROLLER PART on the MDS, then press NEXT MENU.

6. Follow the steps presented on the MDS and DRBIII which will allow the DRBIII to obtain the current part number of the controller.

7.

The MDS will display the part number of the controller on the vehicle and the appropriate replacement part number, then press NEXT MENU tobegin programming.

If the controller on the vehicle has already been updated or programmed, a NO UPDATES AVAILABLE message will be displayed. Check the partnumber of the controller on the vehicle and compare it to the part number displayed. If the part numbers match and the controller update has beenverified, proceed to Step 9.

8. The MDS and DRBIII will prompt for any operator action needed during the remainder of the programming process.

: NOTE

THE FOLLOWING STEPS ARE REQUIRED BY LAW.

Chrysler Authorized Software Update Label

9.

Type the necessary information on the "Authorized Software Update Label" and attach it to the PCM and cover the label with a clear plasticsticker.

> Relays and Modules > Relays and Modules - Powertrain Management > Relays and Modules - Computers and Control Systems > Powertrain Control Module <--> [Engine

Control Module] > Component Information > Technical Service Bulletins > All Technical Service Bulletins for Powertrain Control Module: > 182395 > Jun > 95 > PCM -

Cold Start Sag/Hesitation or Backfire/Pop > Page 57

RAM 2500 Van V6-239 3.9L Magnum (1995)

Chrysler Authorized Modification Label

10. Type the necessary information on the Authorized Modification Label and attach the label near the VECI Label.

POLICY: Reimbursable within the provisions of the warranty.
TIME ALLOWANCE: Module. Powertrain Control Reprogram

Labor Operation No: 08-19-42-97 (1995 BR) 0.5 Hrs.

Replace Module. Powertrain Control and Reprogram 08-19-42-98 (1994 BR)

0.7 Hrs.

FAILURE CODE: FM - Flash Module

> Relays and Modules > Relays and Modules - Powertrain Management > Relays and Modules - Computers and Control Systems > Powertrain Control Module <--> [Engine Control Module] > Component Information >

Technical Service Bulletins > Page 58

Powertrain Control Module: Locations

PCM Location B Series Vans

The Powertrain Control Module is mounted in the center of the firewall.(PCM)

> Relays and Modules > Relays and Modules - Powertrain Management > Relays and Modules - Computers and Control Systems > Powertrain Control Module <--> [Engine Control Module] > Component Information >

Diagrams > Diagram Information and Instructions

Powertrain Control Module: Diagram Information and Instructions

Circuit Function

Circuit Identification

All circuits in the diagrams use an alpha/numeric code to identify the wire and its function. To identify which circuit code applies to a system, refer to theCircuit Identification Code Chart. This chart shows the main circuits only and does not show the secondary codes that may apply to some models.

Circuit Information

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Control Module] > Component Information > Diagrams > Diagram Information and Instructions > Page 61

RAM 2500 Van V6-239 3.9L Magnum (1995)

Wire Code Identification

Wire Color Code Chart

Each wire shown in the diagrams contains a code which identifies the main circuit, part of the main circuit, gauge of wire, and color.

Connector Information

Connector Identification

Connectors shown in the diagrams are identified using the international standard arrows for male and female terminals. A connector identifier is placednext to the arrows to indicate the connector number.

For viewing connector pin-outs, with two or more terminals, refer to Connector Pin-Outs Index, which identifies the connector by number and providesterminal numbering, circuit identification, wire colors, and functions.

> Relays and Modules > Relays and Modules - Powertrain Management > Relays and Modules - Computers and Control Systems > Powertrain Control Module <--> [Engine

Control Module] > Component Information > Diagrams > Diagram Information and Instructions > Page 62

RAM 2500 Van V6-239 3.9L Magnum (1995)

All connectors are viewed from the terminal end unless otherwise specified. To find the connector location in the vehicle, refer to Connector LocationsIndex, which uses the connector identification number from the wiring diagrams to provide a figure number reference.

Electrostatic Discharge (ESD) Sensitive Devices

Electrostatic Discharge Symbol

(ESD)

All Electrostatic Discharge sensitive components are solid state and a symbol is used to indicate this. When handling any component with thissymbol, comply with the following procedures to reduce the possibility of electrostatic charge build-up on the body and inadvertent discharge into thecomponent. If it is not known whether the part is ESD sensitive, assume that it is.

1. Always touch a known good ground before handling the part. This should be repeated while handling the part, especially after sliding across a seat,
sitting down from a standing position, or walking a distance.

2. Avoid touching electrical terminals of the part, unless instructed to do so by a written procedure.3. When using a voltmeter, be sure to connect the ground lead first.4. Do not remove the part from its protective packing until it is time to install the part.5. Before removing the part from its package, ground the package to a known good ground on the vehicle.

Fuses

CAUTION:

When replacing a blown fuse, it is important to replace it with a fuse having the correct amperage rating. The use of a fuse with a ratingother than that indicated may result in an electrical overload. If a properly rated fuse continues to blow, it indicates a problem that should be corrected.

Notes, Cautions and Warnings

Additional important information is presented in three ways: Notes, Cautions, and Warnings.

NOTES

are used to help describe how switches or components operate to complete a particular circuit. They are also used to indicate differentconditions that may appear on the vehicle. For example, an up-to and after condition.

are used to indicate information that could prevent making an error that may damage the vehicle.CAUTIONS

WARNING:

- ALWAYS WEAR SAFETY GLASSES FOR EYE PROTECTION.

- USE SAFETY STANDS ANYTIME A PROCEDURE REQUIRES BEING UNDER A VEHICLE.

­BE SURE THAT THE IGNITION SWITCH ALWAYS IS IN THE OFF POSITION, UNLESS THE PROCEDURE REQUIRES IT TOBE ON.

­SET THE PARKING BRAKE WHEN WORKING ON ANY VEHICLE. AN AUTOMATIC TRANSMISSION SHOULD BE IN PARK.A MANUAL TRANSMISSION SHOULD BE IN NEUTRAL.

- OPERATE THE ENGINE ONLY IN A WELL-VENTILATED AREA.

- KEEP AWAY FROM MOVING PARTS WHEN THE ENGINE IS RUNNING, ESPECIALLY THE FAN AND BELTS.

> Relays and Modules > Relays and Modules - Powertrain Management > Relays and Modules - Computers and Control Systems > Powertrain Control Module <--> [Engine

Control Module] > Component Information > Diagrams > Diagram Information and Instructions > Page 63

RAM 2500 Van V6-239 3.9L Magnum (1995)

WARNINGS

provide information to prevent personal injury and vehicle damage. Below is a list of general warnings that should be followed any time avehicle is being serviced.

­TO PREVENT SERIOUS BURNS, AVOID CONTACT WITH HOT PARTS SUCH AS THE RADIATOR, EXHAUST MANIFOLD(S),TAIL PIPE, CATALYTIC CONVERTER, AND MUFFLER.

­DO NOT ALLOW FLAME OR SPARKS NEAR THE BATTERY. GASES ARE ALWAYS PRESENT IN AND AROUND THEBATTERY.

- ALWAYS REMOVE RINGS, WATCHES, LOOSE HANGING JEWELRY, AND LOOSE CLOTHING.

Symbols

> Relays and Modules > Relays and Modules - Powertrain Management > Relays and Modules - Computers and Control Systems > Powertrain Control Module <--> [Engine

Control Module] > Component Information > Diagrams > Diagram Information and Instructions > Page 64

RAM 2500 Van V6-239 3.9L Magnum (1995)

Symbol Identification

Various symbols are used throughout the Wiring Diagrams. These symbols can be identified by referring to the Symbol Identification chart.

Take-Outs

The abbreviation is used in the component location Group to indicate a point at which the wiring harness branches out to a component.T/O

How to Find System & Component Diagrams

Group Index

When trying to find the diagram for a specific component or system, use the information or the under Alphabetic Index to Wiring Diagrams Electrical

Group Index Diagrams By Sheet Number

Whenever a reference exists to another sheet or figure, find the corresponding diagram using the , , or . The reference number for the subsequent diagram will match a listed group shown.Diagrams By Figure Number

How to Read Wiring Diagrams

Wire Color Code Identification

Wire Color Code Chart

Each wire shown in the diagrams contains a code which identifies the main circuit, part of the main circuit, gauge of wire, and color. The color is shownas a two-letter code, which can be identified by referring to the Wire Color Code chart. If the wire has a tracer, and it is a standard color, an asterisk willfollow the main wire color. If the tracer is non-standard, the main wire color will have a slash after it, followed by the tracer color.(/)

Connector and Terminal Replacement

> Relays and Modules > Relays and Modules - Powertrain Management > Relays and Modules - Computers and Control Systems > Powertrain Control Module <--> [Engine

Control Module] > Component Information > Diagrams > Diagram Information and Instructions > Page 65

RAM 2500 Van V6-239 3.9L Magnum (1995)

six inches

1/2 inch

1. Disconnect battery.2. Disconnect the connector (that is to be repaired) from its mating half/component.3. Cut off the existing wire connector directly behind the insulator. Remove of tape from the harness.4. Stagger cut all wires on the harness side at intervals.5. Remove of insulation from each wire on the harness side. 1 inch

Stagger Cutting Wires (Typical)

6. Stagger cut the matching wires on the repair connector assembly in the opposite order as was done on the harness side of the repair. Allow extra
length for soldered connections. Check that the overall length is the same as the original.

1 inch

7. Remove of insulation from each wire.8. Place a piece of heat-shrink tubing over one side of the wire. Be sure the tubing will be long enough to cover and seal the entire repair area.

Wire Repair

9. Spread the strands of the wire apart on each part of the exposed wires (Example 1).

10. Push the two ends of wire together until the strands of wire are close to the insulation (Example 2).11. Twist the wires together (Example 3).12. Solder the connection together using rosin core solder only. 13. Center the heat-shrink tubing over the joint and heat using a heat gun. Heat the joint until the tubing is tightly sealed and sealant comes out of bothDo not use acid core solder.

ends of the tubing.

1-1/2 inches 2 inches

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14. Repeat steps 8 through 13 for each wire.15. Re-tape the wire harness starting behind the connector and past the repair.16. Re-connect the repaired connector.17. Connect the battery and test all affected systems.

Connector Replacement

1. Disconnect the battery.2. Disconnect the connector (that is to be repaired) from its mating half/component.

Connector Locking Wedge

3. Remove the connector locking wedge, if required.

Terminal Removal

Terminal Removal Using Special Tool

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RAM 2500 Van V6-239 3.9L Magnum (1995)

4. Position the connector locking finger away from the terminal using the proper pick from Special Tool Kit . Pull on the wire to remove the6680

terminal from the connector.

5. Reset the terminal locking tang, if it has one.6. Insert the removed wire in the same cavity on the repair connector.7. Repeat steps 4 through 6 for each wire in the connector, being sure that all wires are inserted into the proper cavities.8. Insert the connector locking wedge into the repaired connector, if required.9. Connect the connector to its mating half/component.

10. Connect the battery and test all affected systems.

Diode Replacement

Diode Identification

Do not use acid core solder.

1. Disconnect the battery.2. Locate the diode in the harness and remove the protective covering.3. Remove the diode from the harness, pay attention to the current flow direction. 4. Remove the insulation from the wires in the harness. Only remove enough insulation to solder in the new diode.5. Install the new diode in the harness, making sure current flow is correct.6. Solder the connection together using rosin core solder only. 7. Tape the diode to the harness using electrical tape, making sure the diode is completely sealed from the elements.8. Re-connect the battery and test affected systems.

Terminal Replacement

1. Disconnect the battery.2. Disconnect the connector being repaired from its mating half/component.

Connnector Locking Wedge Tab (Typical)

3. Remove the connector locking wedge, if required.

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RAM 2500 Van V6-239 3.9L Magnum (1995)

Terminal Removal

Terminal Removal Using Special Tool

4. Position the connector locking finger away from the terminal using the proper pick from Special Tool Kit . Pull on the wire to remove the6680

terminal from the connector.

6 inches

1 inch

1 inch

5. Cut the wire from the back of the connector.6. Remove of insulation from the wire on the harness side.7. Select a wire from the terminal repair assembly that best matches the color of the wire being repaired.8. Cut the repair wire to the proper length and remove of insulation.9. Place a piece of heat-shrink tubing over one side of the wire. Be sure the tubing will be long enough to cover and seal the entire repair area.

Wire Repair

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RAM 2500 Van V6-239 3.9L Magnum (1995)

Do not use acid core solder.

10. Spread the strands of the wire apart on each part of the exposed wires (Example 1).11. Push the two ends of wire together until the strands of wire re close to the insulation (Example 2).12. Twist the wires together (Example 3).13. Solder the connection together using rosin core solder only. 14. Center the heat-shrink tubing over the joint and heat using a heat gun. Heat the joint until the tubing is tightly sealed and sealant comes out of both

ends of the tubing.

1-1/2 inches 2 inches

15. Insert the repaired wire into the connector.16. Install the connector locking wedge, if required and re-connect the connector to its mating half/component.17. Re-tape the wire harness starting behind the connector and past the repair.18. Connect the battery and test all affected systems.

Terminal/Connector Repair-Molex Connectors

1. Disconnect the battery.2. Disconnect the connector from its mating half/component.

Molex Connector Repair

3. Insert the terminal releasing special tool into the terminal end of the connector.6742

Using Special Tool 6742

6742

4. Using special tool , release the locking fingers on the terminal.5. Pull on the wire to remove it from the connector.6. Repair or replace the connector or terminal, as necessary.

Wiring Repair

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Wire Repair

When replacing or repairing a wire, it is important that the correct gauge be used as shown in the wiring diagrams. The wires must also be held securelyin place to prevent damage to the insulation.

1. Disconnect the battery negative cable.

2. Remove of insulation from each end of the wire.1 inch

3. Place a piece of heat-shrink tubing over one side of the wire. Be sure the tubing will be long enough to cover and seal the entire repair area.

4. Spread the strands of the wire apart on each part of the exposed wires (Example 1).

5. Push the two ends of wire together until the strands of wire are close to the insulation (Example 2).

6. Twist the wires together (Example 3).

7. Solder the connection together using rosin core solder only. Do not use acid core solder.

8. Center the heat-shrink tubing over the joint and heat using a heat gun. Heat the joint until the tubing is tightly sealed and sealant comes out of both
ends of the tubing.

9. Secure the wire to the existing ones to prevent chafing or damage to the insulation.

10. Connect the battery and test all affected systems.

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Diagrams > Diagram Information and Instructions > Page 71

Powertrain Control Module: Diagnostic Aids

Intermittent and Poor Connections

Most intermittent electrical problems are caused by faulty electrical connections or wiring. It is also possible for a sticking component or relay to cause aproblem. Before condemning a component or wiring assembly check the following items.

- Connectors are fully seated

- Spread terminals, or terminal push out

- Terminals in the wiring assembly are fully seated into the connector/component and locked in position

- Dirt or corrosion on the terminals. Any amount of corrosion or dirt could cause an intermittent problem

- Damaged connector/component casing exposing the item to dirt and moisture

- Wire insulation that has rubbed through causing a short to ground

- Some or all of the wiring strands broken inside of the insulation covering.

- Wiring broken inside of the insulation

Troubleshooting Tests

Before beginning any tests on a vehicle's electrical system, use the wiring diagrams to study the circuit. Also refer to Troubleshooting Wiring Problemssection.

Testing For Voltage

Testing For Voltage

1. Connect the ground lead of a voltmeter to a known good ground.2. Connect the other lead of the voltmeter to the selected test point. The vehicle ignition may need to be turned ON to check voltage. Refer to the
appropriate test procedure.

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RAM 2500 Van V6-239 3.9L Magnum (1995)

Testing For Continuity

Testing For Continuity

1. Remove the fuse for the circuit being checked or disconnect the battery.2. Connect one lead of the ohmmeter to one side of the circuit being tested.3. Connect the other lead to the other end of the circuit being tested. Low or no resistance means good continuity.

Testing For A Short To Ground

6 to 8 Inches

1. Remove the fuse and disconnect all items involved with the fuse.2. Connect a test light or a voltmeter across the terminals of the fuse.3. Starting at the fuse block, wiggle the wiring harness every and watch the voltmeter/test light.4. If the voltmeter registers voltage or the test light glows, there is a short-to-ground in that general area of the wiring harness.

Testing For A Short-to-ground On Fuses Powering Several Loads

1. Refer to the wiring diagrams and disconnect or isolate all items on the fuse circuit.2. Replace the blown fuse.3. Supply power to the fuse by turning ON the ignition switch or re-connecting the battery.4. Start connecting the items in the fuse circuit, one at a time. When the fuse blows, the circuit with the short-to-ground has been isolated.

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RAM 2500 Van V6-239 3.9L Magnum (1995)

Testing For Voltage Drop

Testing For Voltage Drop

1. Connect the positive lead of the voltmeter to the side of the circuit closest to the battery.2. Connect the other lead of the voltmeter to the other side of the switch or component.

3. Operate the item.4. The voltmeter will show the difference in voltage between the two points.

Troubleshooting Tools
TROUBLESHOOTING TOOLS

When diagnosing a problem in an electrical circuit, there are several common tools necessary. These tools are listed and explained below.

- - This is a test wire used to connect two points of a circuit. It can be used to bypass an open in a circuit.Jumper Wire

WARNING: NEVER USE A JUMPER WIRE ACROSS A LOAD, SUCH AS A MOTOR, CONNECTED BETWEEN A BATTERYFEED AND GROUND.

- Voltmeter

- This instrument is used to check for voltage on a circuit. Always connect the black lead to a known good ground and the red lead tothe positive side of the circuit.

CAUTION:

Most of the electrical components used in today's vehicle are solid state. When checking voltages in these circuits, use a meter with a or greater impedance.10 megohm

- Ohmmeter

- This instrument is used to check the resistance between two points of a circuit. Low or no resistance in a circuit can mean goodcontinuity or a shorted circuit.

CAUTION:

10 megohm

Most of the electrical components used in today's vehicle are solid state. When checking resistance in these circuits, use a meter witha or greater impedance. In addition, be sure the power is disconnected from the circuit. Circuits that are powered-up by the vehicleelectrical system can cause damage to the equipment and provide false readings.

Probing Tool

- Probing Tools 6807

- These tools are used for probing terminals in connectors. Select the proper size tool from Special Tool Package and insert itinto the terminal being tested. Use the other end of the tool to insert the meter probe.

Troubleshooting Wiring Problems

When troubleshooting wiring problems there are six steps which can aid in the procedure. The steps are listed and explained below. Always check fornon-factory items added to the vehicle before doing any diagnosis. If the vehicle is equipped with these items, disconnect them to verify these add-onitems are not the cause of the problem.

1. Verify the problem.

2. Verify any related symptoms. Do this by performing operational checks on components that are in the same circuit. Refer to the wiring diagrams.

3. Analyze the symptoms. Use the wiring diagrams to determine what the circuit is doing, where the problem most likely is occurring and where the
diagnosis will continue.

4. Isolate the problem area.

5. Repair the problem.

6. Verify proper operation. For this step check for proper operation of all items on the repaired circuit. Refer to the wiring diagrams.

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Powertrain Control Module: Connector Views

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RAM 2500 Van V6-239 3.9L Magnum (1995)

Connector Pin Outs (Part 17 Of 45)

Connector Pin Outs (Part 18 Of 45)

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Description and Operation > General Operation

Powertrain Control Module: Description and OperationGeneral Operation

(PCM)

(WOT)

As input signals to the Powertrain Control Module change, The PCM adjusts its response that it sends to the output devices. For example, thePCM must calculate a different injector pulse width and ignition timing for idle than it does for wide open throttle . Likewise the PCM changesignition timing to compensate for different operating conditions. There are nine modes of operation that determine how the PCM responds to the variousinput signals.
Modes of operation are separated into two different types.

- OPEN LOOP- CLOSED LOOP

Open Loop

During modes the PCM receives input signals and responds only to preset PCM programming. Input from the oxygen (02) sensor isnot monitored during Open Loop modes.

Closed Loop

During modes the PCM monitors the oxygen sensor input. This input indicates to the PCM whether or not the calculated injectorpulse width results in the ideal air/fuel ratio of 14.7 parts of air to 1 part of fuel. By monitoring the exhaust oxygen content, using the oxygensensor, the PCM can "fine tune" the injector pulse width to achieve optimum fuel economy and performance combined with low emission levels.

The sequential multi-point fuel injection system has the following modes of operation:(SFI)

- Ignition switch ON- Engine start-up (CRANK)- Engine warm-up- Idle- Cruise - Acceleration- Deceleration- Wide Open Throttle (WOT)- Ignition switch OFF

The ignition switch ON, engine start-up (CRANK), engine warm-up, deceleration, acceleration, wide open throttle, and ignition switch OFF modesare Open Loop modes.
The Cruise and Idle modes, with the engine at operating temperature, are Closed Loop modes.

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Description and Operation > General Operation > Page 78

Powertrain Control Module: Description and OperationLimp-In Mode

If the Malfunction Indicator Lamp , is illuminated during vehicle operation, the vehicle has entered limp-in.NOTE: (MIL)

PURPOSE

Allows reduced vehicle operation, if one or more inputs fail. (The vehicle should be driven to a service facility as soon as possible.)

OPERATION

(PCM)

In Limp-in mode the Powertrain Control Module substitutes the input of an alternate sensor, for that of the failed sensor, and continues tomonitor the faulty sensor input.
If the faulty sensor input returns within limits, and remains within limits long enough, the PCM will resume normal operation.

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Description and Operation > General Operation > Page 79

Powertrain Control Module: Description and OperationModes of Operation

Acceleration

This is a OPEN LOOP mode.

- The Powertrain Control Module recognizes an abrupt increase in throttle position or MAP pressure, as a demand for increased engine(PCM)

output to accelerate vehicle.

- The PCM increases injector pulse width, in response to increased fuel demand.

Cruise

This is a CLOSED LOOP mode.

With engine at operating temperature, the Powertrain Control Module receives inputs from:(PCM)

(CMP)

(ECT)

(MAP)

(IAT)

(CKP)

- Air Conditioning Control Position- Battery voltage- Camshaft position sensor- Engine coolant temperature sensor- Manifold absolute pressure sensor- Intake air temperature sensor- Crankshaft position sensor- Throttle position sensor - Heated oxygen sensor (TPS) (HO2S)

Based on these inputs the PCM will:

- Apply voltage to the injectors. The PCM then controls injection sequence and pulse width by switching individual injector ground paths on
and off.

- Monitor oxygen sensors and fine tune air/fuel ratio by varying injector pulse width.- Adjust engine idle speed through the IAC motor.- Adjust ignition timing.- Operate A/C Compressor Clutch relay (if selected).

Deceleration

This is an OPEN LOOP mode.

During deceleration the the Powertrain Control Module receives inputs from:(PCM)

Based on these inputs the PCM will:

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RAM 2500 Van V6-239 3.9L Magnum (1995)

(CMP)

(ECT)

(MAP)

(IAT)

(CKP)

- Air Conditioning Control Position- Battery voltage- Camshaft position sensor- Engine coolant temperature sensor- Manifold Absolute Pressure sensor- Intake air temperature sensor- Crankshaft position sensor- Throttle Position Sensor (TPS)

- Adjust engine idle speed through the IAC motor.- Adjust ignition timing.- Operate A/C Compressor Clutch relay (if selected).- Ignore oxygen sensor input. The PCM will enter fuel cut-off strategy (under hard deceleration).- Determine proper injector pulse width and continue injection (under normal deceleration).

Engine Start-Up

This is an OPEN LOOP mode.

When the starter motor is engaged, the Powertrain Control Module receives input from:(PCM)

(CKP)
(ECT)

(IAT)

(TPS) (CMP)

- Battery voltage- Crankshaft position sensor- Engine coolant temperature sensor- Intake air temperature sensor- Throttle position sensor - Camshaft position sensor- Starter relay

Based on these inputs, the PCM will:

- Monitor crankshaft position sensor. If no signal is received within 3 seconds, the PCM will shut down the fuel injection system.- Supply the injectors with a ground path, firing all injectors until the PCM determines crankshaft position.- Determine proper ignition timing.

Engine Warm-Up

This is an OPEN LOOP mode.

During engine warm-up, the Powertrain Control Module receives input from:(PCM)

(CKP)
(ECT)

(IAT)

(MAP)

(TPS) (CMP)

- Battery voltage- Crankshaft position sensor- Engine coolant temperature sensor- Intake air temperature sensor- Manifold absolute pressure sensor- Throttle position sensor - Camshaft position sensor- A/C select switch

Based on these inputs the PCM will:

- Apply voltage to the injectors. The PCM then controls injection sequence and pulse width by switching individual injector ground paths on
and off.

- Adjust engine idle speed through the IAC motor.- Adjust ignition timing.- Operate A/C Compressor Clutch relay (if selected).- Operate the Up-Shift indicator light.- Begin to monitor oxygen sensor. When engine is at operating temperature, the system will leave warm up mode and go into closed loop
operation.

Idle

This is a CLOSED LOOP mode.

With engine idling at operating temperature, the Powertrain Control Module receives inputs from:(PCM)

(CMP)

(ECT)

(MAP)

(IAT)

(CKP)

- Air Conditioning Control Position- Battery voltage- Camshaft position sensor- Engine coolant temperature sensor- Manifold Absolute Pressure sensor- Intake air temperature sensor- Crankshaft position sensor- Throttle Position Sensor - Heated oxygen sensor (TPS) (HO2S)

Based on these inputs the PCM will:

- Apply voltage to the injectors. The PCM then controls injection sequence and pulse width by switching individual injector ground paths on
and off.

- Monitor oxygen sensors and fine tune air/fuel ratio by varying injector pulse width.- Adjust engine idle speed through the IAC motor.- Adjust ignition timing.- Operate A/C Compressor Clutch relay (if selected).

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Ignition Switch Off

When the ignition switch is OFF the Powertrain Control Module will stop operating the:(PCM)

(ASD)

- Fuel injectors- Ignition coil- Automatic shutdown relay- Fuel pump relay.

Ignition Switch On

This is an OPEN LOOP mode.

When the sequential multi-point fuel injection system is activated by the ignition switch, the following actions occur:(SFI)

(PCM) (IAC)
(MAP)

- The Powertrain Control Module prepositions the idle air control motor.- The PCM reads atmospheric air pressure from the manifold absolute pressure sensor and calculates the basic fuel strategy.- The PCM monitors the throttle position sensor and engine coolant temperature sensor input. The PCM uses these inputs to(TPS) (ECT)

modify fuel strategy.

(IAT)

(ASD)

- Intake air temperature sensor is monitored.- The Automatic Shutdown relay is energized for 3 seconds.- Fuel pump is energized for 1 second, unless engine is running or cranking.- Oxygen sensor heating element is energized.- Up shift indicator light is illuminated (M/T only).

Wide Open Throttle

This is an OPEN LOOP mode.

During wide open throttle operation the Powertrain Control Module receives the following inputs:(PCM)

(CMP)

(ECT)

(MAP)

(IAT)

(CKP)

- Battery voltage- Camshaft position sensor- Engine coolant temperature sensor- Manifold absolute pressure sensor- Intake air temperature sensor- Crankshaft position sensor- Throttle position sensor (TPS)

Based on these inputs the PCM will:

- Apply voltage to the injectors. The PCM then controls injection sequence and pulse width by switching individual injector ground paths on
and off. Oxygen sensor input is ignored. The PCM will supply a predetermined amount of additional fuel.

- Monitor oxygen sensor and fine tune air/fuel ratio by varying injector pulse width.- Adjust ignition timing.- De-energize A/C Compressor Clutch relay (if selected).

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Information > Locations

Automatic Shut Down (ASD) Relay: Locations

Relay Location

The Auto Shutdown Relay is located in the engine compartment near the 50-WAY bulkhead connector.(ASD)

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Information > Locations > Page 85

Automatic Shut Down (ASD) Relay: Diagrams

Relay Terminals

RELAY TERMINAL NUMBERS

The relay terminal numbers from can be found on the bottom of the relay:

^ Terminal number 30 is connected to battery voltage and can be switched or B + (hot) at all times.
^ Terminal number 87A is connected (a circuit is formed) to terminal 30 in the de-energized (normally OFF) position.
^

Terminal number 87 is connected (a circuit is formed) to terminal 30 in the energized (ON) position. Terminal number 87 then suppliesbattery voltage to the component being operated.

^ Terminal number 86 is connected to a switched (+)power source.
^ Terminal number 85 is grounded by the PCM.

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Information > Locations > Page 86

Automatic Shut Down (ASD) Relay: Description and Operation

(ASD) (PCM)

When the ignition switch is in the START or RUN position, it connects battery voltage from circuit A1 to the A21 circuit. Circuit A21 supplies batteryvolt- age to the coil side of the Automatic Shut Down relay. The Powertrain Control Module supplies ground for the coil side of the relayon circuit K51. Circuit K51 connects to cavity 51 of the PCM.

(PDC)

When the PCM grounds the ASD relay, contacts inside the relay close and connect circuit A14 from fuse 1 in the Power Distribution Center tocircuit A142. Circuit A142 splices to the generator field terminal, fuel injectors, ignition coil, and heated oxygen sensor. Circuit A142 also connects tocavity 57 of the PCM. This input tells the PCM that the ASD relay has energized.

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Information > Testing and Inspection > Auto Shutdown (ASD) Relay

Automatic Shut Down (ASD) Relay: Testing and InspectionAuto Shutdown (ASD) Relay
OPERATION

(ASD)

The following operations/tests apply to these relays only: Automatic Shutdown and Fuel Pump. For operations/tests on all other relays,refer to the appropriate section of this service manual.

Relay Terminals

RELAY TERMINAL NUMBERS

The relay terminal numbers from can be found on the bottom of the relay:

^ Terminal number 30 is connected to battery voltage and can be switched or B + (hot) at all times.
^ Terminal number 87A is connected (a circuit is formed) to terminal 30 in the de-energized (normally OFF) position.
^

Terminal number 87 is connected (a circuit is formed) to terminal 30 in the energized (ON) position. Terminal number 87 then suppliesbattery voltage to the component being operated.

^ Terminal number 86 is connected to a switched (+)power source.