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Pinpoint Test Ai: Abs Module Communication Concern With Pcm

  1. Normal Operation and Fault Conditions 

    With the ignition ON, the PCM sends messages to the ABS module over the FD-CAN. If the ABS module does not receive these messages within the allotted time frame or if the messages contain invalid data, the module sets a DTC. This can be due to a PCM failure, a circuit failure on the network or an excessive load on the network. For information on the messages sent to the ABS module by the PCM, REFER to: Anti-Lock Brake System (ABS) and Stability Control .

    The TCM is an internal component of the PCM.

    DTC Fault Trigger Conditions 

    DTC Description Fault Trigger Condition
    ABS U0100:00 Lost Communication With ECM/PCM 'A': No Sub Type Information This DTC sets when the ABS module does not receive any messages from the PCM within the allowed time.
    ABS U0401:00 Invalid Data Received from ECM/PCM A: No Sub Type Information This DTC sets when the ABS module receives invalid data in any of the following messages: powertrain message counter, powertrain message checksum, gear lever position or REVERSE gear status.
    ABS U0401:64 Invalid Data Received from ECM/PCM A: Signal Plausibility Failure This DTC sets when the ABS module receives invalid data in the driven wheel torque messages.
    ABS U0401:86 Invalid Data Received from ECM/PCM A: Signal Invalid This DTC sets when the ABS module receives invalid data in the accelerator pedal message, driven wheel torque message, transmission requested gear message or PARK status message.
    ABS U0402:86 Invalid Data Received from TCM: Signal Invalid This DTC sets when the ABS module receives invalid data in the neutral tow command or the selectable drive mode switch type message.

    Possible Causes 

    • Network communication concern
    • PCM

  2. AI1 CHECK THE PCM (POWERTRAIN CONTROL MODULE) COMMUNICATION

    • Ignition ON.

    • Using a diagnostic scan tool, carry out the Network Test.

    • Using a diagnostic scan tool, retrieve the DTC s from the vehicle.
      NOTE: DTC s may be displayed from previous diagnostic actions.

    Does the PCM pass the Network Test? 

    Yes  RETRIEVE and RECORD all PCM Diagnostic Trouble Codes (DTCs). REFER to: Electronic Engine Controls . If there are no PCM Diagnostic Trouble Codes (DTCs), GO to  AI3
    No  GO to  AI2

  3. AI2 CHECK THE GATEWAY MODULE (GWM) COMMUNICATION

    • Ignition ON.

    • Using a diagnostic scan tool, carry out the Network Test.

    Does the GWM pass the Network Test? 

    Yes  DIAGNOSE the PCM does not communicate with the diagnostic scan tool. REFER to: Controller Area Network (CAN) Module Communications Network .
    No  DIAGNOSE the GWM does not communicate with the diagnostic scan tool, REFER to: Controller Area Network (CAN) Module Communications Network .

  4. AI3 CHECK THE ABS (ANTI-LOCK BRAKE SYSTEM) FOR THE LOST COMMUNICATION DIAGNOSTIC TROUBLE CODE (DTC)

    NOTE: When retrieving DTC s, ignore all historical or CMDTCs.

    • Using a diagnostic scan tool, clear the ABS module DTC s.

    • Put the ABS module in sleep mode by performing the following steps:

      • With ALL doors closed, set the ignition from ON to OFF.
      • Disconnect the diagnostic scan tool.
      • Open the door, exit the vehicle and close the door.
      • Wait a minimum of 90 seconds for the ABS module to enter sleep mode.

    • Ignition ON.

    • Using a diagnostic scan tool, carry out the ABS self-test

    Are any DTC s from the DTC Fault Trigger Conditions Table present and active in the ABS module? 

    Yes  GO to  AI4
    No  The system is operating correctly at this time. The DTC may have been set due to high network traffic or an intermittent fault condition

  5. AI4 REVIEW THE ABS (ANTI-LOCK BRAKE SYSTEM) MODULE SELF-TEST FOR VOLTAGE-RELATED DTC (DIAGNOSTIC TROUBLE CODE) S

    • Using a diagnostic scan tool, review the recorded DTC s from the ABS self-test.

    Is DTC U3003:16 or U3003:17 present? 

    Yes  For DTC U3003:16, GO to Pinpoint Test A  For DTC U3003:17, GO to Pinpoint Test F 
    No  GO to  AI5

  6. AI5 CHECK FOR GWM (GATEWAY MODULE A) DTC (DIAGNOSTIC TROUBLE CODE) S

    • Ignition ON.

    • Using a diagnostic scan tool, carry out the GWM module self-test.

    Are any GWM DTCs present? 

    Yes  DIAGNOSE the GWM Diagnostic Trouble Codes (DTCs). REFER to: Controller Area Network (CAN) Module Communications Network .
    No  GO to  AI6

  7. AI6 CHECK FOR PCM (POWERTRAIN CONTROL MODULE) DTC (DIAGNOSTIC TROUBLE CODE) S

    • Using a diagnostic scan tool, carry out the PCM self-test.

    Are any DTC s present? 

    Yes  DIAGNOSE the PCM DTCs. REFER to: Electronic Engine Controls .
    No  GO to  AI7

  8. AI7 CHECK FOR OTHER CAUSES OF COMMUNICATION NETWORK CONCERN

    NOTE: If new modules were installed prior to the DTC being set, the module configuration can be incorrectly set during the PMI or the PMI may not have been carried out.

    • Check the vehicle service history for recent service actions related to the PCM or the ABS module. If recent service history is found:

      • Verify the correct replacement module was installed. HVBOM may be used to verify correct part fitment.
      • Verify the configuration of replacement module was correct. Re-configure the module using as-built data if prior configuration is suspect.
      • Verify the module was not obtained from a like vehicle and installed into customer vehicle. Return the swapped module to source vehicle and obtain new replacement module.

    • Operate the system and determine if the observable symptom is still present.

    Is the observable symptom still present? 

    Yes  GO to  AI8
    No  The system is operating correctly at this time. The concern may have been due to incorrect parts replacement procedures or incorrect module configuration.

  9. AI8 CHECK FOR COMMUNICATION DTC (DIAGNOSTIC TROUBLE CODE) S SET IN OTHER MODULES

    • Using a diagnostic scan tool, retrieve the DTC s from the vehicle.
      NOTE: DTC s may be displayed from previous diagnostic actions.

    Is any DTC from the fault trigger table set in 1 or more modules in addition to the ABS module? 

    Yes  GO to  AI9
    No  GO to  AI10

  10. AI9 CHECK FOR CORRECT PCM (POWERTRAIN CONTROL MODULE) MODULE OPERATION

    • Put the ABS module in sleep mode by performing the following steps:

      • With ALL doors closed, set the ignition from ON to OFF.
      • Disconnect the diagnostic scan tool.
      • Open the door, exit the vehicle and close the door.
      • Wait a minimum of 90 seconds for the ABS module to enter sleep mode.

    • Disconnect ABS module connector C135, if not previously disconnected.

    • Disconnect PCM B connector if not previously disconnected.

    • Disconnect PCM E connector if not previously disconnected.

    • Disconnect GWM connector C2431A, if not previously disconnected.

    • Using a good light source, INSPECT all Disconnected electrical connectors for the following:

      • Corrosion - INSTALL new connector or terminal and clean the module pins
      • Damaged or bent pins - INSTALL new terminals or pins
      • Pushed-out pins - INSTALL new pins as necessary
      • Spread terminals - INSTALL new terminals as necessary

    • Connect GWM connector C2431A. Make sure the connector seats and latches correctly.

    • Connect PCM E connector. Make sure the connector seats and latches correctly.

    • Connect PCM B connector. Make sure the connector seats and latches correctly.

    • Connect ABS module connector C135. Make sure the connector seats and latches correctly.

    • Operate the system and determine if the concern is still present.

    Is the concern still present? 

    Yes  CHECK OASIS for any service articles: TSB, GSB, SSM or FSA. If a service article exists for this concern, DISCONTINUE this test and FOLLOW the service article instructions. If no service article exists for this concern,
    INSTALL a new Powertrain Control Module (PCM). Only available in the on-line service information RVC: 
    Generate RVC only works in single-step view Generate RVC requires VIN entry 
    REFER to: Powertrain Control Module (PCM) .
    No  The system is operating correctly at this time. The concern may have been caused by a loose or corroded connector. ADDRESS the root cause of any connector or pin issues.

  11. AI10 CHECK FOR CORRECT ABS (ANTI-LOCK BRAKE SYSTEM) MODULE OPERATION

    • Ignition OFF.

    • Disconnect ABS module C135, if not previously disconnected.

    • Using a good light source, INSPECT all Disconnected electrical connectors for the following:

      • Corrosion - INSTALL new connector or terminal and clean the module pins
      • Damaged or bent pins - INSTALL new terminals or pins
      • Pushed-out pins - INSTALL new pins as necessary
      • Spread terminals - INSTALL new terminals as necessary

    • Connect the ABS module connector. Make sure it seats and latches correctly.

    • Operate the system and determine if the concern is still present.

    Is the concern still present? 

    Yes  CHECK OASIS for any service articles: TSB, GSB, SSM or FSA. If a service article exists for this concern, DISCONTINUE this test and FOLLOW the service article instructions. If no service articles address this concern, INSTALL a new EBB. REFER to: Electric Brake Booster (EBB) .
    No  The system is operating correctly at this time. The concern may have been caused by a loose or corroded connector. ADDRESS the root cause of any connector or pin issues.
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