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Pinpoint Test Av : U0155

  1. NOTE: The Inverter System Controller (ISC) is referred to as the SOBDMC (Secondary On-Board Diagnostic Control Module C) in the scan tool.

    Normal Operation and Fault Conditions 

    REFER to: Electric Powertrain Control - System Operation and Component Description .

    DTC Fault Trigger Conditions 

    DTC Description Fault Trigger Condition
    SOBDMC U0155:00 Lost Communication With Instrument Panel Cluster (IPC) Control Module: No Sub Type Information This DTC sets when messages are missing from the IPC.

    Possible Sources 

    • Communications network concern
    • IPC

  2. AV1 VERIFY THE CONCERN

    • Ignition ON.

    • Verify there is an observable symptom present.

    Is an observable symptom present? 

    Yes  GO to  AV2
    No  CLEAR the DTC. The system is operating correctly at this time. The DTC may have been set due to high network traffic or an intermittent fault condition.

  3. AV2 VERIFY THE DIAGNOSTIC SCAN TOOL COMMUNICATES WITH THE IPC (INSTRUMENT PANEL CLUSTER)

    • Connect the diagnostic scan tool to the vehicle.

    • Attempt to establish a vehicle session using the diagnostic scan tool.

    Can a vehicle session be established? 

    Yes  GO to  AV3
    No  REFER to: Communications Network .

  4. AV3 CHECK FOR NON-NETWORK DIAGNOSTIC TROUBLE CODES (DTCS)

    • Using a diagnostic scan tool, carry out the Inverter System Controller (ISC) self-test.

    Are any non-network DTCs present? 

    Yes  DIAGNOSE all non-network DTCs first. REFER to Diagnostic Trouble Code (DTC) Chart .
    No  GO to  AV4

  5. AV4 CHECK FOR NON-NETWORK IPC (INSTRUMENT PANEL CLUSTER) DIAGNOSTIC TROUBLE CODES (DTCS)

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

    Are any non-network DTCs present? 

    Yes  REFER to Instrument Panel And Interior Switches Illumination .
    No  GO to  AV5

  6. AV5 CHECK THE INVERTER SYSTEM CONTROLLER (ISC) AND IPC (INSTRUMENT PANEL CLUSTER) CALIBRATION LEVELS

    • Verify the Inverter System Controller (ISC) and the IPC are at the latest calibration levels.

    Are the Inverter System Controller (ISC) and the IPC at the latest calibration levels? 

    Yes  GO to  AV6
    No  UPDATE the Inverter System Controller (ISC) or IPC to the latest calibration level.

  7. AV6 RECHECK FOR DTC (DIAGNOSTIC TROUBLE CODE) U0155

    • Using a diagnostic scan tool, clear the Inverter System Controller (ISC) DTCs.

    • Ignition OFF.

    • Ignition ON.

    • Wait 10 seconds.

    • Using a diagnostic scan tool, carry out the self-test for the Inverter System Controller (ISC).

    Is DTC U0155 present? 

    Yes  GO to  AV7
    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.

  8. AV7 CHECK FOR OTHER CAUSES OF NETWORK COMMUNICATION 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 IPC and the Inverter System Controller (ISC). If recent service history is found:

      • verify correct replacement module was installed

        • vehicle parts build list may be used to verify correct part fitment

      • 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 vehicle with concern

        • 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  AV8
    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. AV8 CHECK FOR CORRECT IPC (INSTRUMENT PANEL CLUSTER) OPERATION

    • Ignition OFF.

    • Disconnect and inspect the IPC connectors.

    • Repair:

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

    • Reconnect the IPC connectors. Make sure they seat and latch correctly.

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

    Is the concern still present? 

    Yes  CHECK OASIS for any applicable 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, REFER to: Communications Network .
    No  The system is operating correctly at this time. The concern may have been caused by module connections. ADDRESS the root cause of any connector or pin issues.
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