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Home >> Infiniti >> 2004 >> FX45 >> Repair and Diagnosis >> Engine Performance >> Engine Control System >> DTC P1780 Shift Change Signal >> Diagnostic Procedure
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Diagnostic Procedure

  1. Check DTC With TCM 

    Check DTC with TCM. Refer to TROUBLE DIAGNOSIS .

    OK or NG

    1. OK: go to 2.
    2. NG: Perform trouble shooting relevant to DTC indicated.

  2. Check TCM Function 

    Refer to TROUBLE DIAGNOSIS .

    OK or NG

    1. OK: go to 3.
    2. NG: Replace TCM. Refer to PRECAUTIONS .

  3. Replace ECM 
    1. Replace ECM.
    2. Perform initialization of IVIS (NATS) system and registration of all IVIS (NATS) ignition key IDs. Refer to ECM RE-COMMUNICATING FUNCTION .
    3. Perform ACCELERATOR PEDAL RELEASED POSITION LEARNING  .
    4. Perform THROTTLE VALVE CLOSED POSITION LEARNING  .
    5. Perform IDLE AIR VOLUME LEARNING  .
    1. Inspection end