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Pinpoint Test C: DTC U0155

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

    Normal Operation and Fault Conditions 

    The IPC, GSM and BCM use information contained in messages on the HS-CAN.

    DTC Fault Trigger Conditions 

    DTC Description Fault Trigger Condition
    GSM U0155:00 Lost Communication With Instrument Panel Cluster (IPC) Control Module: No Sub Type Information This DTC sets if the GSM does not receive some or all of an expected message from the IPC.

    Possible Sources 

    • Connectors damaged or pushed-out terminals, circuitry open, shorted to power or shorted to ground
    • BCM fuses 13 and 19 (7.5A)
    • IPC

  2. C1 CHECK THE COMMUNICATION NETWORK

    • Ignition ON.

    • NOTE: If a GSM self-test is performed, make sure the drivers door is closed and locked.

      Using the diagnostic scan tool, perform the network test.

    Does the IPC module pass the network test? 

    Yes  GO to  C2
    No  To diagnose the module does not respond to the scan tool, REFER to: Controller Area Network (CAN) Module Communications Network
     
  3. C2 CHECK FOR GSM (GEAR SHIFT MODULE) DIAGNOSTIC TROUBLE CODES (DTCS)

    • Clear all DTCs.

    • Using the diagnostic scan tool, perform the GSM self-test.

    Is DTC U0155 present? 

    Yes  GO to  C3
    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. C3 RETRIEVE THE RECORDED DIAGNOSTIC TROUBLE CODES (DTCS) FROM THE GSM (GEAR SHIFT MODULE) SELF-TEST

    • Check for DTCs from the self-test.

    Are any GSMDTCs present? 

    Yes  REFER to the GSMDTC chart and diagnose those DTCs first.
    No  GO to  C4
  5. C4 RETRIEVE THE RECORDED DIAGNOSTIC TROUBLE CODES (DTCS) FROM THE IPC (INSTRUMENT PANEL CLUSTER) SELF-TEST

    • Check for DTCs from the self-test.

    Is DTC U3000:49 present? 

    Yes  REFER to: Instrumentation, Message Center and Warning Chimes
     
    No  GO to  C5
  6. C5 CHECK FOR DTC (DIAGNOSTIC TROUBLE CODE) U0155 SET IN OTHER MODULES

    • Using the diagnostic scan tool, perform the self-test for all modules.

    • Retrieve the DTCs from all modules.

    Is DTC U0155 present in the PCM or SCCM? 

    Yes  CHECK OASIS for any applicable service articles: TSB, GSB (general service bulletin), SSM (special service message) or FSA (Field Service Action). 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 IPC. Refer to INSTRUMENT PANEL CLUSTER (IPC)
    No  If the reporting module is the GSM, INSTALL a new GSM. REFER to: Gear Shift Module (GSM)