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Pinpoint Test Av: Abs (Anti-Lock Brake System) Module Communication Concern With GSM (Gear Shift Module)

  1. Normal Operation and Fault Conditions 

    With the ignition ON, the GSM sends messages to the ABS module over the HS-CAN2. 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 GSM 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 GSM, REFER to: DIAGNOSIS AND TESTING .

    DTC Fault Trigger Conditions 

    DTC Description Fault Trigger Condition
    ABS U0103:00 Lost Communication With Gear Shift Control Module A: No Sub Type Information This DTC sets when the ABS module does not receive any messages from the GSM within the allowed time.
    ABS U0404:00 Invalid Data Received from Gear Shift Control Module A: No Sub Type Information This DTC sets when the ABS module does not receive any messages from the GSM within the allowed time.

    Possible Causes 

    • Network communication concern
    • GSM

  2. AV1 CHECK THE COMMUNICATION NETWORK

    • Ignition ON.

    • Press the Read Vehicle Information button to view the results of the modules communicating on the network.

    • Press Read Vehicle Information button to retrieve DTC's from the vehicle.
      NOTE: DTC's may be displayed from previous diagnostic actions.

    • Read vehicle information.

    Does the GSM pass the network test? 

    Yes  RETRIEVE and RECORD all GSMDTC's. REFER to: External Controls . If there are no DTC's in the GSM. GO to  AV2
    No  DIAGNOSE the no communication with the GSM. REFER to: External Controls .

  3. AV2 RECHECK FOR THE ABS (ANTI-LOCK BRAKE SYSTEM) MODULE DTCS

    • Clear the ABS 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.

    • Carry out the ABS module self-test.

    • Record all ABS module DTC's.

    Do any of the DTC's listed in the DTC Fault Trigger Conditions table return? 

    Yes  GO to  AV3
    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.

  4. AV3 CHECK FOR VOLTAGE DTCS 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  AV4

  5. AV4 CHECK FOR DTCS IN THE GSM (GEAR SHIFT MODULE)

    • Carry out the GSM self-test.

    • Record all DTC's from the GSM self-test.

    Are any DTC's present? 

    Yes  DIAGNOSE the GSMDTC's. REFER to: External Controls in the appropriate Automatic Transmission External Controls article.
    No  GO to  AV5

  6. AV5 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 GSM module or 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 concern is still present.

    Is the observable symptom still present? 

    Yes  GO to  AV6
    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.

  7. AV6 CHECK FOR COMMUNICATION DTCS IN OTHER MODULES

    • Ignition ON.

    • Clear the ABS module DTC's.

    • Press Read Vehicle Information button to retrieve DTC's from the vehicle.

    • Read the vehicle information.

    Is DTC U0103:xx or U0404:xx set in 1 or more modules in addition to the ABS module? 

    Yes  GO to  AV7
    No  For Electric brake booster: GO to  AV8
    For all others: Test is complete and no faults were found.

  8. AV7 VERIFY GSM (GEAR SHIFT 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.

    • Disconnect GSM connector C3532.

    • 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 GSM connector C3532. Make sure the connector seats and latches correctly.

    • Connect ABS 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 services articles address this concern, INSTALL a new GSM. REFER to: Gear Shift Module (GSM) .
    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.

  9. AV8 VERIFY 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

    • Disconnect ABS module connector C135.

    • Disconnect GSM connector C3532.

    • 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 GSM connector C3532. 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 articles address this concern, INSTALL a new EBB unit (HCU and ABS module assembly). REFER to: Electric Brake Booster (EBB) . REFER to: Electric Brake Booster (EBB) - Full Hybrid Electric Vehicle (FHEV)/Plug-In Hybrid Electric Vehicle (PHEV) .
    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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