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Pinpoint Test L: Invalid Data Received From Another Module

  1. Refer to MODULE COMMUNICATIONS NETWORK for schematic and connector information.

    Normal Operation and Fault Conditions 

    The GSM expects to receive network data from other modules on HS-CAN2. The GSM will set a DTC if it receives an invalid or incomplete message from another module. Incomplete or corrupted messages typically result from high network traffic preventing the complete message from being received within the calibrated time limit.

    DTC Fault Trigger Conditions 

    DTC Description Fault Trigger Condition
    GSM U0401:00 Invalid Data Received from ECM/PCM A: No Sub Type Information This DTC indicates the GSM is receiving messages from the SOBDMC, but the SOBDMC is reporting faults in key signals.
    GSM U0422:00 Invalid Data Received From Body Control Module: No Sub Type Information This DTC indicates the GSM is receiving messages from the BCM, but the BCM is reporting faults in key signals.
    GSM U0504:00 Invalid Data Received From "Door Control Module E": No Sub Type Information This DTC indicates the GSM is receiving messages from the DCME, but the DCME is reporting faults in key signals.

    Possible Sources 

    • High network traffic event
    • Incorrect PMI
    • Connectors damaged or pushed-out terminals, corrosion, loose wires and missing or damaged seals
    • Suspect module

  2. L1 CHECK THE SUSPECT MODULE FOR DIAGNOSTIC TROUBLE CODES (DTCS)

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

    Are any diagnostic trouble codes (DTCs) present in the suspect module? 

    Yes  RESOLVE those diagnostic trouble codes first. REFER to the Master DTC Chart.
    No  GO to  L2

  3. L2 ATTEMPT TO DUPLICATE THE DTC (DIAGNOSTIC TROUBLE CODE)

    NOTE: If a GSM self-test is carried out, the driver door must be fully closed. A false P166B DTC may set if the driver door is not fully closed during the self-test.

    • Using a diagnostic scan tool, clear all diagnostic trouble codes from the GSM.

    • Road test the vehicle.

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

    Did the invalid data DTC set again? 

    Yes  GO to  L3
    No  The system is operating correctly at this time. The concern may have been caused by a high network traffic event.

  4. L3 CHECK FOR OTHER CAUSES OF COMMUNICATION CONCERNS

    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 suspect module or to the GSM. If recent service history is found:

      • verify correct replacement module was installed

        • HVBOM may be used to verify correct part application

      • verify the configuration of replacement module was correct

        • re-configure 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

    Were any causes of a communication concern found in the vehicle service history? 

    Yes  PROGRAM or INSTALL a new module as necessary.
    No  GO to  L4

  5. L4 INSPECT ALL IN-LINE CAN (CONTROLLER AREA NETWORK) CONNECTORS

    • Ignition OFF.

    • Refer to MODULE COMMUNICATIONS NETWORK for schematic and connector information. Disconnect all in-line CAN connectors between the GSM and the suspect module.

    • Using a good light source, inspect all  disconnected electrical connectors for the following:

      • corrosion (install new connector or terminals - clean module pins)
      • damaged or bent pins - install new terminals/pins
      • pushed-out pins - install new pins as necessary
      • spread terminals - install new terminals as necessary

    Are any connector or pin issues present? 

    Yes  REPAIR any connector or pin issues.
    No  GO to  L5

  6. L5 CHECK THE SUSPECT MODULE FOR CORRECT OPERATION

    • Ignition OFF.

    • Disconnect and inspect all suspect module connectors.

    • Repair:

      • corrosion (install new connector or terminals - clean module pins)
      • damaged or bent pins - install new terminals/pins
      • pushed-out pins - install new pins as necessary

    • Connect the suspect module connectors. Make sure they seat and latch correctly.

    • Operate the system and verify the concern is still present.

    Is the concern still present? 

    Yes  CHECK for an applicable TSB, GSB, SSM, or FSA. If a service bulletin exists for this concern, discontinue this test and follow bulletin instructions. If none address this concern, INSTALL a new suspect module. For U0401, INSTALL a new SOBDMC. REFER to: Inverter System Controller [SOBDMC] . For U0422, INSTALL a new BCM. REFER to: Body Control Module (BCM) . For U0504, INSTALL a new DCME. REFER to: Front Door Latch .
    No  The system is operating correctly at this time. The concern may have been caused by module or network connections. ADDRESS the root cause of any connector or pin issues.
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