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Pinpoint Test Cl: Abs Module Communication Concern With APIM

  1. Normal Operation and Fault Conditions 

    With the ignition ON, the APIM sends messages to the ABS module over the HS-CAN3 through the GWM. 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 an APIM 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 APIM, REFER to: Anti-Lock Brake System (ABS) and Stability Control - System Operation and Component Description .

    When a drive mode is selected through the FCDIM, a message is sent to the APIM indicating the selected drive mode. The APIM sends a message out to other modules along the HS-CAN3 through the GWM indicating a specific drive mode has been selected. The other modules modify their operating parameters according to the drive mode selected.

    DTC Fault Trigger Conditions 

    DTC Description Fault Trigger Condition
    ABS P05D3:86 Driver Mode Select Switch 'A' Range/Performance: Signal Invalid This DTC sets when the drive mode message from the APIM indicates an invalid signal.
    ABS U0253:00 Lost Communication With Accessory Protocol Interface Module: No Sub Type Information This DTC sets when the ABS module has not received any messages from the APIM in the allotted time.
    ABS U0554:00 Invalid Data Received From Accessory Protocol Interface Module: No Sub Type Information This DTC sets when the ABS module receives messages from the APIM, but the messages contain invalid data.

    Possible Causes 

    • Wiring, terminals or connectors
    • Network communication concern
    • APIM

  2. CL1 CHECK THE COMMUNICATION NETWORK

    • Ignition ON.

    • Using a diagnostic scan tool, perform a network test.

    Does the APIM pass the network test? 

    Yes  Diagnose the APIM DTCs. REFER to: Information and Entertainment System . If there are no APIM DTCs, GO to  CL3
    No  GO to  CL2

  3. CL2 CHECK THE GWM (GATEWAY MODULE A) COMMUNICATION

    • Review the results of the modules communicating on the network from the previous step.

    Did the GWM pass the network test? 

    Yes  DIAGNOSE the APIM 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. CL3 RECHECK THE ABS (ANTI-LOCK BRAKE SYSTEM) MODULE FOR THE LOST COMMUNCATION DTC (DIAGNOSTIC TROUBLE CODE) S

    • Using a diagnostic scan tool, clear the ABS module Diagnostic Trouble Codes (DTCs).

    • 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.

    • Carry out the ABS self-test.

    Are any of the DTCs listed in the Fault Trigger Conditions still present? 

    Yes  GO to  CL4
    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. CL4 CHECK FOR VOLTAGE DTC (DIAGNOSTIC TROUBLE CODE) S IN THE ABS (ANTI-LOCK BRAKE SYSTEM) MODULE

    • Review the recorded DTCs from the ABS module 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  CL5

  6. CL5 CHECK FOR GWM (GATEWAY MODULE A) DIAGNOSTIC TROUBLE CODES (DTCS)

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

    Are any GWM Diagnostic Trouble Codes (DTCs) present? 

    Yes  DIAGNOSE any GWM DTCs. REFER to: Controller Area Network (CAN) Module Communications Network .
    No  GO to  CL6

  7. CL6 CHECK FOR APIM (ACCESSORY PROTOCOL INTERFACE MODULE) DTC (DIAGNOSTIC TROUBLE CODE) S

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

    Are any DTCs present in the APIM? 

    Yes  Diagnose the APIM DTCs. REFER to: Information and Entertainment System .
    No  GO to  CL7

  8. CL7 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 APIM or ABS. 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  CL8
    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. CL8 CHECK FOR COMMUNICATION DIAGNOSTIC TROUBLE CODES (DTCS) IN OTHER MODULES

    • Ignition ON.

    • Using a diagnostic scan tool retreve all Diagnostic Trouble Codes (DTCs).

    Is any DTC from the Fault Trigger Conditions Table present in one or more modules in addition to the ABS module? 

    Yes  GO to  CL9
    No  GO to  CL10

  10. CL9 CHECK FOR CORRECT APIM (ACCESSORY PROTOCOL INTERFACE 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.

    • 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 APIM C2383A. Make sure it seats and latches correctly.

    • Connect GWM C2431A. 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 exist, INSTALL a new APIM REFER to: Accessory Protocol Interface Module (APIM) .
    INSTALL a new Accessory Protocol Interface Module (APIM).
    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. CL10 CHECK FOR CORRECT ABS (ANTI-LOCK BRAKE SYSTEM) 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.

    • Using a good light source, INSPECT the electrical connector 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 C2431A. Make sure it seats and latches correctly.

    • Connect ABS C135. 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 module. 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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