LEMON Manuals: Even more car manuals for everyone
Home >> Ford >> 2022 >> Mustang Mach 1 Premium, Automatic Trans >> Repair and Diagnosis >> External Pages >> Different variant/trim >> Section 22 (Automatic Transmission - 7-Speed Automatic Transmission - Tr9070 (Diagnosis And Testing, General Procedures, Removal And Installation)) >> Diagnosis And Testing >> DTC Chart and Pinpoint Tests >> Pinpoint Tests >> Pinpoint Test P: DTC U0103

Pinpoint Test P: DTC U0103

WARNING: This page is about a different variant/trim than selected.
  1. Refer to MODULE COMMUNICATIONS NETWORK for schematic and connector information.

    Normal Operation and Fault Conditions 

    The TCM and the GSM communicate through messages sent on HS-CAN. The TCM is on HS-CAN1 and the GSM is on HS-CAN2, which communicate through GWM. The TCM and GSM also send redundant messages over the dedicated transmission CAN.

    DTC Fault Trigger Conditions 

    DTC Description Fault Trigger Condition
    TCM U0103:00 Lost Communication With Gear Shift Control Module A: No Sub Type Information The TCM sets this DTC if the GSM data messages received from the GSM over the HS-CAN are missing for longer than 2 seconds.

    Possible Sources 

    • Communication concern
    • Battery voltage concern
    • GSM
    • TCM

  2. P1 CHECK THE TCM (TRANSMISSION CONTROL MODULE) FOR DIAGNOSTIC TROUBLE CODES (DTCS)

    • Using a diagnostic scan tool, retrieve all diagnostic trouble codes (DTCs) from the TCM.

    Is DTC U0103 present? 

    Yes  If diagnostic trouble codes (DTCs) U0115, U0121, U0140 and U0155 are all also present, indicating the HS-CAN bus is down, GO to Pinpoint Test U  Otherwise, GO to  P2
    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.

  3. P2 VERIFY THE SCAN TOOL COMMUNICATES WITH THE GSM (GEAR SHIFT MODULE)

    • Ignition ON.

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

    Did the GSM complete the self-test? 

    Yes  GO to  P3
    No  To diagnose a GSM does not respond to the scan tool concern, REFER to: Communications Network

  4. P3 CHECK THE GSM (GEAR SHIFT MODULE) FOR DIAGNOSTIC TROUBLE CODES (DTCS)

    • Using a diagnostic scan tool, retrieve all diagnostic trouble codes (DTCs) from the GSM self-test.

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

    Yes  RESOLVE all GSM diagnostic trouble codes (DTCs) first. REFER to: External Controls
    No  GO to  P4

  5. P4 CHECK THE TRANSMISSION CAN (CONTROLLER AREA NETWORK) CIRCUITS FOR AN OPEN

    • Ignition OFF.

    • Disconnect Mode select switch C284 .

    • Inspect the connectors for damaged or pushed-out terminals.

    Are the resistances less than 3 ohms? 

    Yes  GO to  P5
    No  REPAIR the circuit.

  6. P5 CHECK THE TRANSMISSION CAN (CONTROLLER AREA NETWORK) CIRCUITS FOR A SHORT TO GROUND

    • Measure:
      Positive Lead Measurement / Action Negative Lead
      C1750A-44
      GFD718917Courtesy of FORD MOTOR COMPANY
      		 Ground
      C1750A-45
      GFD718917Courtesy of FORD MOTOR COMPANY
      		 Ground

    Are the resistances greater than 10, 000 ohms? 

    Yes  Connect all connectors that have been disconnected. GO to  P6
    No  REPAIR the circuit.

  7. P6 CHECK THE TCM (TRANSMISSION CONTROL MODULE) FOR DIAGNOSTIC TROUBLE CODES (DTCS)

    • Using a diagnostic scan tool, clear all diagnostic trouble codes (DTCs) from the TCM.

    • Road test the vehicle.

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

    Is DTC U0103 still present? 

    Yes  If any TCM voltage supply or internal module diagnostic trouble codes (DTCs) are present, RESOLVE those first. REFER to the Diagnostic Trouble Code (DTC) Chart . Otherwise, GO to  P7
    No  The system is operating correctly at this time. The DTC may have been set due to high network traffic, or by a connector or pin issue.

  8. P7 CHECK FOR GSM (GEAR SHIFT MODULE) COMMUNICATION DIAGNOSTIC TROUBLE CODES (DTCS) SET IN OTHER MODULES

    • Using a diagnostic scan tool, retrieve all continuous memory diagnostic trouble codes (CMDTCs) from all modules.

    Are GSM communication diagnostic trouble codes (DTCs) present in other modules? 

    Yes  GO to  P8
    No  GO to  P9

  9. P8 CHECK FOR CORRECT GEAR SHIFT MODULE OPERATION

    • Ignition OFF.

    • Disconnect and inspect all GSM 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

    • Reconnect the GSM 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 OASIS for any applicable TSBs. If a TSB exists for this concern, DISCONTINUE this test and FOLLOW TSB instructions. If no TSBs 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 module connections. ADDRESS the root cause of any connector or pin issues.

  10. P9 CHECK FOR CORRECT TCM (TRANSMISSION CONTROL MODULE) OPERATION

    • Ignition OFF.

    • Disconnect and inspect the TCM 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

    • Reconnect the TCM 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 OASIS for any applicable TSBs. If a TSB exists for this concern, DISCONTINUE this test and FOLLOW TSB instructions. If no TSBs address this concern, INSTALL a new TCM. REFER to: Transmission Control Module (TCM) 
    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.
scientia non olet · About LEMON Manuals