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Pinpoint Test D: DTC P0814

  1. Refer to Transmission Controls for schematic and connector information.

    Normal Operation and Fault Conditions 

    The GSM monitors the gear select buttons, and the illumination of each gear indicator LED.

    DTC Fault Trigger Conditions 

    DTC Description Fault Trigger Condition
    GSM P0814:00 Transmission Range Display Circuit: No Sub Type Information This DTC sets if the GSM detects the wrong gear selection LED is illuminated.

    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

  2. D1 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  D2
    No  CHARGE or INSTALL a new battery if necessary. REFER to: Battery .

  3. D2 CHECK GSM CALIBRATION LEVEL

    • VERIFY the GSM calibration is at the latest level.

    Is the GSM calibration at the latest level? 

    Yes  GO to  D3
    No  PROGRAM the GSM with the latest calibration. REFER to: Module Programming .

  4. D3 CHECK THE GSM (GEAR SHIFT MODULE) DIAGNOSTIC TROUBLE CODES (DTCS)

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

    • Using a diagnostic scan tool, clear all GSM diagnostic trouble codes (DTCs).

    • Ignition OFF.

    • Wait 10 seconds.

    • Start the engine.

    • Press each gear select button, pausing after each one.

    • Select PARK.

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

    Is DTC P0814 or P0915 still present? 

    Yes  If DTC P0562 or P0563 is also present, RESOLVE those diagnostic trouble codes (DTCs) first. Otherwise, GO to  D4
    No  The fault is not present at this time and might be intermittent.

  5. D4 CHECK FOR CORRECT GSM (GEAR SHIFT MODULE) OPERATION

    • Ignition OFF.

    • Disconnect and inspect GSM C3245.

    • 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 GSM C3245. Make sure it seats and latches 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.
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