Engine Controls Self-Diagnostics - Diesel: Diagnosis Dodge Pickup R2500

SELF-DIAGNOSTIC SYSTEM

Note. When battery is disconnected, Engine Control Module (ECM) is disconnected or replaced, or Accelerator Pedal Position Sensor (APPS) has been disconnected or replaced, ECM must be programmed to match the APPS. For ECM programming, see ENGINE CONTROL MODULE under PROGRAMMING.

Note. If replacing PCM, PCM must be properly programmed. See POWERTRAIN CONTROL MODULE under PROGRAMMING.

Note. Self-diagnostic tests are written specifically for Chrysler's Diagnostic Readout Box (DRBIII®) scan tool, which may be referred to as DRB or DRBIII during testing procedures. A generic scan tool may not be capable of performing all necessary test functions.

ON-BOARD DIAGNOSTICS

Note. Malfunction Indicator Light (MIL) may also be referred to as CHECK ENGINE light.

MIL is located on instrument cluster, just below WATER-IN-FUEL light directly below the tachometer and is displayed as an engine icon. When ignition is first turned on, MIL should come on and remain on for 2 seconds to verify bulb and circuit operation, and then go off.

Note. If MIL does not come on and remain on for 2 seconds and then go off when ignition is first turned on, check instrument cluster for diagnosis of MIL. See ANALOG INSTRUMENT PANELS - RAM PICKUP article in ACCESSORIES & EQUIPMENT.

The Engine Control Module (ECM) and Powertrain Control Module (PCM) monitor several circuits and components in the powertrain system. ECM is used to control fuel and emission systems and PCM is used to primarily control charging system, transmission, A/C compressor clutch operation and vehicle speed control functions. If ECM or PCM senses a problem with a monitored circuit often enough to indicate a problem, a Diagnostic Trouble Code (DTC) will be stored in ECM or PCM. DTCs are the result of a system or circuit malfunction, but do not directly identify the failed component or components. If malfunction affects vehicle emissions, a DTC will be stored in ECM and MIL will be turned on and remain on steady and ECM will enter limp-in mode. In limp-in mode, the ECM substitutes values for failed component and provides continuous engine operation. If problem exists which does not affect vehicle emissions, a DTC will be stored in ECM or PCM but MIL will not be turned on. Certain DTCs may also store a companion DTC, meaning that if a certain DTC is stored in the ECM or PCM, the same DTC will be stored in the opposite control module. Any circuit or component that is associated with limp-in mode will cause a DTC to be stored in ECM and illuminate the MIL after one trip. Any circuit or component that is not associated with limp-in mode will cause DTC to be stored in ECM and illuminate the MIL after 2 trips. The ECM or PCM will turn off MIL when malfunction is not detected during 3 consecutive trips.

The ECM or PCM might not store a DTC for a monitored circuit even though a malfunction has occurred. This may happen because one of the criteria for DTC has not been met. For example, assume criteria for DTC requires ECM to monitor a specified circuit only when engine operates between 750 RPM and 2000 RPM. If the sensor output circuit becomes shorted to ground when engine is operating at 2400 RPM, DTC will not be stored, as short to ground occurred at 2400 RPM which exceeds the limit when the circuit was monitored.

DTCs may be retrieved for system diagnosis. See RETRIEVING DIAGNOSTIC TROUBLE CODES . System malfunctions are identified as either hard failures or intermittent failures. For additional information on hard failures or intermittent failures, see HARD FAILURES and INTERMITTENT FAILURES .

DIAGNOSTIC PROCEDURE

The procedures contained in this article include specifications, instructions and graphics needed to diagnose PCM powertrain system. The diagnostics are based on the failure condition or symptom being present at the time of diagnosis. Use the following recommendations

1. First make sure the DRBIII® is communicating with the appropriate modules; i.e., if the DRBIII® displays a No Response condition, you must diagnose the condition first before proceeding. See «BASIC DIAGNOSTIC PROCEDURES - RAM PICKUP - DIESEL»(ref-157961) article (no response with a no-start condition) or appropriate BODY CONTROL MODULES article in ACCESSORIES & EQUIPMENT (all other no response conditions).
2. Using DRBIII® scan tool read Diagnostic Trouble Codes (DTC). See «RETRIEVING DIAGNOSTIC TROUBLE CODES»(ref-157446-S06819456672003081400000) .
3. If no DTCs are present, identify the customer complaint and diagnose by symptom. See «TROUBLE SHOOTING - NO CODES - RAM PICKUP - DIESEL»(ref-158825) article.
4. If any DTCs are present, perform the appropriate diagnostic test. See «DIAGNOSTIC TROUBLE CODE DEFINITIONS»(ref-157446-S28685869512003081400000) .

RETRIEVING DIAGNOSTIC TROUBLE CODES

Note. Ensure battery is fully charged before retrieving diagnostic trouble codes.

1. Ensure ignition off. Connect DRBIII® scan tool to Data Link Connector (DLC). DLC is located below driver's side of instrument panel. (Scheme 736)
2. Turn ignition on with engine off. Using scan tool manufacturer's instructions, read and record Diagnostic Trouble Codes (DTC). Certain DTCs may also store a companion DTC, meaning that if a certain DTC is stored in the Engine Control Module (ECM) or Powertrain Control Module (PCM), the same DTC will be stored in the opposite control module. If DTCs are stored, identify DTC and perform appropriate test for displayed DTCs. See «DIAGNOSTIC TROUBLE CODE DEFINITIONS»(ref-157446-S28685869512003081400000). Once all repairs are made, ensure DTCs are cleared from ECM and PCM. See «CLEARING DIAGNOSTIC TROUBLE CODES»(ref-157446-S20988338232003081400000).
3. On any scan tool, if scan tool displays NO RESPONSE for ECM and/or PCM, perform appropriate procedure under «SCAN TOOL COMMUNICATIONS»(ref-157446-S37297313822003081400000). If scan tool will not power up, check for loose cable connections or bad cable. If cable connections or cable are defective, repair or replace components as necessary and then recheck for DTCs. If cable connections and cable are okay, using DVOM, measure voltage at cavity No. 16 (Pink wire) on DLC. Voltage should be at least 11 volts. If voltage is not as specified, check for defective fuse No. 12 (10-amp), as this fuse supplies voltage from battery to cavity No. 16 on DLC. Fuse No. 12 is located in junction block on end of driver's side of instrument panel, near door opening. If necessary, check wiring circuit between fuse No. 12 and the battery. For R2500, see «COMPUTER DATA LINES»(ref-154277-S32401829482003051200000) in SYSTEM WIRING DIAGRAMS article in ELECTRICAL. For R2500, see «POWER DISTRIBUTION»(ref-154277-S13749694872003051200000) in SYSTEM WIRING DIAGRAMS article in ELECTRICAL. For R3500, see «COMPUTER DATA LINES»(ref-154278-S42669479682003051200000) in SYSTEM WIRING DIAGRAMS article in ELECTRICAL. For R3500, see «POWER DISTRIBUTION»(ref-154278-S09053572152003051200000) in SYSTEM WIRING DIAGRAMS article in ELECTRICAL. If voltage exists at cavity No. 16 (Pink wire) on DLC but scan tool will not power up and blank screen exists, it may be necessary to ensure that good ground exists at DLC terminals No. 4 (Black/Light Green wire) or No. 5 (Black/Tan wire). For ground circuit wiring, refer to: For R2500, see «GROUND DISTRIBUTION»(ref-154277-S33758792602003051200000) in SYSTEM WIRING DIAGRAMS article in ELECTRICAL. For R3500, see «GROUND DISTRIBUTION»(ref-154278-S09311448242003051200000) in SYSTEM WIRING DIAGRAMS article in ELECTRICAL.
4. If scan tool display is not visible, try adjusting contrast. Low ambient temperatures will effect display screen.
5. If scan tool displays an error message, (i.e., USER-REQUESTED COLD BOOT or USER-REQUESTED WARM BOOT), follow scan tool manufacturer's instructions. If scan tool displays a bus failure, this indicates either a scan tool failure or bus failure. To diagnose and correct bus failures, see appropriate diagnostic and repair procedure under COMMUNICATIONS under SYSTEM TESTS in BODY CONTROL MODULES - RAM PICKUP article in ACCESSORIES & EQUIPMENT.
6. If no DTCs are displayed, refer to one of the following: For driveability problems, perform appropriate symptom test located in «TROUBLE SHOOTING - NO CODES - RAM PICKUP - DIESEL»(ref-158825) article. For no-start problems, perform appropriate no-start test in «BASIC DIAGNOSTIC PROCEDURES - RAM PICKUP - DIESEL»(ref-157961) article. For individual system and component tests, perform appropriate procedure in «SYSTEM & COMPONENT TESTING - RAM PICKUP - DIESEL»(ref-157962) article. For additional speed control problems and servicing information, see appropriate CRUISE CONTROL SYSTEMS article in ACCESSORIES & EQUIPMENT. For additional charging system problems and servicing information, see appropriate GENERATORS & REGULATORS article in ELECTRICAL.

Note. If MIL remains on steady and no DTCs exist, check instrument cluster for diagnosis of MIL. See ANALOG INSTRUMENT PANELS - RAM PICKUP article in ACCESSORIES & EQUIPMENT.

Using Scan Tool

Connect DRBIII® scan tool to Data Link Connector (DLC). DLC is located below driver's side of instrument panel. (Scheme 736) Turn ignition on with engine off. Using screen prompts on scan tool, erase DTC from Engine Control Module (ECM) or Powertrain Control Module (PCM). Certain DTCs may also store a companion DTC, meaning that if a certain DTC is stored in the ECM or PCM, the same DTC will be stored in the opposite control module. It may be necessary to clear DTC from both ECM and PCM.

Self-Erasure

After 3 good trips, Powertrain Control Module (PCM) will turn off the MIL. At that time, the PCM will automatically switch the trip counter to a warm-up cycle counter. The PCM will erase DTCs after 40 warm-up cycles if the recent malfunction does not reoccur in that time. For additional information on good trips and warm-up cycles, see TRIP INDICATOR under ON-BOARD DIAGNOSTICS.

Testing

1. Turn ignition on. Using DRBIII® scan tool, attempt to communicate with Powertrain Control Module (PCM). If scan tool communicates with PCM, go to next step. If scan tool does not communicate with PCM, go to «NO RESPONSE FROM ENGINE CONTROL MODULE & POWERTRAIN CONTROL MODULE»(ref-157446-S06535330272003081400000) .
2. Turn ignition off. Check power and grounds for Engine Control Module (ECM). See «CHECKING ENGINE CONTROL MODULE POWER & GROUND CIRCUITS»(ref-157446-S40447916112003081400000) under DIAGNOSTIC CIRCUIT CHECK. Repair as necessary. If power and grounds for ECM are okay, go to next step.
3. Ensure ignition is off. Disconnect ECM harness connector. ECM is located on driver's side of engine, just in front of fuel transfer pump and contains a 50-pin connector. Disconnect scan tool from Data Link Connector (DLC). Using DVOM, measure resistance between ground and terminal No. 39 (Dark Green wire) on ECM harness connector. If resistance is 5 ohms or greater, go to next step. If resistance is less than 5 ohms, repair short to ground in Dark Green wire.
4. Ensure ignition is off. Using DVOM, measure resistance of Dark Green wire between terminal No. 39 on ECM harness connector and terminal No. 6 on DLC. If resistance is less than 5 ohms, go to next step. If resistance is 5 ohms or greater, repair open in Dark Green wire.
5. Ensure ignition is off. Using DVOM, measure resistance of Pink/Dark Blue wire between terminal No. 38 on ECM harness connector and terminal No. 7 on DLC. If resistance is less than 5 ohms, go to next step. If resistance is 5 ohms or greater, repair open in Pink/Dark Blue wire.
6. Replace and program the ECM. See «REMOVAL & INSTALLATION - RAM PICKUP - DIESEL»(ref-157342) article.

1. Turn ignition on. Using DRBIII® scan tool, attempt to communicate with Engine Control Module (ECM). ECM may also be referred to as Cummins Controller. If scan tool communicates with ECM, go to next step. If scan tool does not communicate with ECM, go to «NO RESPONSE FROM ENGINE CONTROL MODULE & POWERTRAIN CONTROL MODULE»(ref-157446-S06535330272003081400000) .
2. Turn ignition off. Check power and grounds for Powertrain Control Module (PCM). See «CHECKING POWERTRAIN CONTROL MODULE POWER & GROUND CIRCUITS»(ref-157446-S02998639002003081400000) under DIAGNOSTIC CIRCUIT CHECK. Repair as necessary. If power and grounds for PCM are okay, go to next step.
3. Ensure ignition is off. Disconnect Gray 32-pin PCM harness connector C3. Disconnect scan tool from Data Link Connector (DLC). Using DVOM, measure resistance between ground and terminal No. 29 (White/Violet wire) on PCM harness connector C3. If resistance is 5 ohms or greater, go to next step. If resistance is less than 5 ohms, repair short to ground in White/Violet wire.
4. Ensure ignition is off. Ensure Gray 32-pin PCM harness connector C3 is still disconnected. Using DVOM, measure resistance of White/Violet wire between terminal No. 29 on PCM harness connector C3 and terminal No. 14 on DLC. If resistance is less than 5 ohms, go to next step. If resistance is 5 ohms or greater, repair open in White/Violet wire.
5. Ensure ignition is off. Ensure Gray 32-pin PCM harness connector C3 is still disconnected. Using DVOM, measure resistance of Pink/Dark Blue wire between terminal No. 27 on PCM harness connector C3 and terminal No. 7 on DLC. If resistance is less than 5 ohms, go to next step. If resistance is 5 ohms or greater, repair open in Pink/Dark Blue wire.
6. Replace and program the PCM. See «REMOVAL & INSTALLATION - RAM PICKUP - DIESEL»(ref-157342) article.

1. Turn ignition off. Check power and grounds for Engine Control Module (ECM) and Powertrain Control Module (PCM). See «DIAGNOSTIC CIRCUIT CHECK»(ref-157446-S03440214342003081400000) . Repair as necessary. If power and grounds for ECM and PCM are okay, go to next step.
2. Ensure ignition is off. Reconnect all disconnected components. Disconnect PCM harness connectors. Turn ignition on. Using DRBIII® scan tool, attempt to communicate with ECM. If scan tool does not communicate with ECM, go to next step. If scan tool communicates with ECM, replace and program the PCM. See «REMOVAL & INSTALLATION - RAM PICKUP - DIESEL»(ref-157342) article.
3. Turn ignition off. Ensure PCM harness connectors are still disconnected. Disconnect scan tool. Disconnect ECM harness connector. Turn ignition on. Using DVOM, measure voltage between ground and terminal No. 7 (Pink/Dark Blue wire) on Data Link Connector (DLC). If voltage is one volt or less, go to next step. If voltage is greater than one volt, repair short to voltage in Pink/Dark Blue wire.
4. Turn ignition off. Ensure scan tool, ECM and PCM are still disconnected. Using a DVOM, measure resistance between terminal No. 7 (Pink/Dark Blue wire) and terminals No. 6 (Dark Green wire) and No. 14 (White/Violet wire) on DLC. If resistance is 5 ohms or greater on both measurements, go to next step. If resistance at either measurement is less than 5 ohms, repair short between SCI transmit circuit and appropriate SCI receive circuit that indicated less than 5 ohms.
5. Ensure ignition is off. Ensure scan tool, ECM and PCM are still disconnected. Using a DVOM, measure resistance between ground and terminal No. 7 (Pink/Dark Blue wire) on DLC. If resistance is 5 ohms or greater, go to next step. If resistance is less than 5 ohms, repair short to ground in Pink/Dark Blue wire.
6. Ensure ignition is off. Ensure scan tool, ECM and PCM are still disconnected. Using DVOM, measure resistance of Pink/Dark Blue wire between terminal No. 38 on ECM harness connector and terminal No. 7 on DLC. If resistance is less than 5 ohms, go to next step. If resistance is 5 ohms or greater, repair open in Pink/Dark Blue wire.
7. Ensure ignition is off. Ensure scan tool is disconnected. Disconnect negative battery cable. Using DVOM, measure resistance between ground and terminals No. 4 (Black/Light Green wire) and No. 5 (Black/Tan wire) at DLC. If resistance is less than 5 ohms on both measurements, go to next step. If resistance at either terminal is 5 ohms or greater, repair open in appropriate ground circuit that indicated 5 ohms or greater.
8. Replace and program the ECM. See «REMOVAL & INSTALLATION - RAM PICKUP - DIESEL»(ref-157342) article.

DIAGNOSTIC CIRCUIT CHECK

Note. This following procedures will check for proper power and ground supply to Engine Control Module (ECM) and Powertrain Control Module (PCM).

Note. For component locations, see COMPONENT LOCATIONS . For connector terminal identification, see CONNECTOR IDENTIFICATION . For circuit identification and wiring diagram, see WIRING DIAGRAMS .

DIAGNOSTIC TROUBLE CODE DEFINITIONS

DIAGNOSTIC TROUBLE CODE DEFINITIONS

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DIAGNOSTIC TESTS

Note. Before diagnosing an engine performance problem, refer to SERVICE PRECAUTIONS under SELF-DIAGNOSTIC SYSTEM before proceeding.

Note. Before performing any testing procedures, check for any related technical service bulletins.

Note. Self-diagnostic tests are written specifically for Chrysler's Diagnostic Readout Box (DRBIII®) scan tool. A generic scan tool may not be capable of performing all necessary test functions.

POWERTRAIN VERIFICATION TEST VER-1

For testing procedures (Scheme 818)

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POWERTRAIN VERIFICATION TEST VER-2

For testing procedures (Scheme 819)

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POWERTRAIN VERIFICATION TEST VER-4

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POWERTRAIN VERIFICATION TEST VER-5

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