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Pinpoint Test I: DTC P0814, P0915

  1. Refer to Wiring Diagrams Transmission Controls - 8F57 for schematic and connector information.

    Normal Operation and Fault Conditions 

    The GSM cannot sense the selected gear position or is unable to boot up upon the ignition being put into the Run position.

    DTC Fault Trigger Conditions 

    DTC Description Fault Trigger Condition
    GSM P0814:00 Transmission Range Display Circuit: No Sub Type Information This CMDTC sets if the GSM is not able to detect selector lever position indicator LED illumination.
    GSM P0915:00 Gear Shift Position Circuit "A" Range/Performance: No Sub Type Information This CMDTC sets if the GSM cannot successfully boot up when the key is turned to the RUN position. Boot failures are typically caused by low system voltage.

    Possible Sources 

    • Connectors damaged or pushed-out terminals, circuitry open or high resistance in the voltage feed wiring to the GSM or a loose ground.
    • Discharged battery/charging system
    • GSM
    • Selector lever cable misadjusted

  2. I1 VERIFY THE BATTERY IS FULLY CHARGED

    • NOTE: If necessary connect the battery charger to the vehicle battery to insure a steady battery voltage while performing this test.

      VERIFY battery is fully charged before proceeding with this test. REFER to: Battery

    Is the battery fully charged? 

    Yes  GO to  I2
    No  CHARGE or INSTALL a new battery if necessary. REFER to: Battery
     

  3. I2 CHECK GSM CALIBRATION LEVEL

    • Ignition ON.

    • Using a diagnostic scan tool, VERIFY the GSM calibration is at the latest level.

    Is the GSM calibration at the latest level? 

    Yes  GO to  I3
    No  REFER to: Module Programming
     

  4. I3 CHECK THE GSM (GEAR SHIFT MODULE) CONTINUOUS MEMORY DTC (DIAGNOSTIC TROUBLE CODE) S

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

    • Clear the CMDTCs.

    • Ignition OFF.

    • Wait 10 seconds.

    • Start the engine.

    • Repeat the GSM self-test.

    Is DTC P0814 or P0915 the only DTC retrieved again? 

    Yes  GO to  I4
    No  GO to  I5

  5. I4 CHECK FOR CORRECT GSM (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.

  6. I5 CHECK POWER CIRCUIT TO GSM FOR AN OPEN

    • Ignition OFF.

    • Disconnect GSM C2503.

    • Ignition ON.

    • Measure:
      Positive Lead Measurement / Action Negative Lead
      C2503-1
      GFD596560Courtesy of FORD MOTOR COMPANY
      		 Ground

    Is the voltage 12.5 volts or greater 

    Yes  GO to  I6
    No  CHECK fuse 12 (7.5A), if OK REPAIR the open circuit, if not OK, REFER to the OEM ELECTRICAL WIRING DIAGRAM INTRODUCTION to diagnose the short circuit.

  7. I6 CHECK GSM GROUND FOR AN OPEN

    • Ignition OFF.

    • NOTE: INSPECT the ground eyelet and verify it is clean and tight.

      Measure:

      Positive Lead Measurement / Action Negative Lead
      C2503-18
      GFD596559Courtesy of FORD MOTOR COMPANY
      		 Ground
      C2503-9
      GFD596559Courtesy of FORD MOTOR COMPANY
      		 Ground

    Is the resistance less than 3 ohms? 

    Yes  GO to  I4
    No  REPAIR the circuit.
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