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Home >> Infiniti >> 2015 >> Q40 RWD >> Repair and Diagnosis >> Electrical >> Body Electrical >> Power Control System (Power Distribution System) >> DTC/Circuit Diagnosis >> Push-Button Ignition Switch >> Diagnosis Procedure
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Diagnosis Procedure

  1. CHECK PUSH-BUTTON IGNITION SWITCH OPERATION

    Press push-button ignition switch and check if it turns to ON.

    Does ignition switch turn to ON?

    YES 

    GO TO STEP 2  .

    NO 

    GO TO STEP 4  .

  2. CHECK IGNITION SWITCH OUTPUT SIGNAL (IPDM E/R)

    1. Disconnect push-button ignition switch connector.
    2. Check voltage between IPDM E/R harness connector and ground.
      (+) (-) Voltage (V)
      (Approx.)
      IPDM E/R
      Connector Terminal
      E5 28 Ground Battery voltage

    Is the inspection result normal?

    YES 

    GO TO STEP 3  .

    NO 

    Replace IPDM E/R. Refer to REMOVAL AND INSTALLATION .

  3. CHECK PUSH-BUTTON IGNITION SWITCH CIRCUIT (IPDM E/R)

    1. Disconnect IPDM E/R connector and BCM connector.
    2. Check continuity between IPDM E/R harness connector and push-button ignition switch harness connector.
      IPDM E/R Push-button ignition switch Continuity
      Connector Terminal Connector Terminal
      E5 28 M50 4 Existed
    3. Check continuity between IPDM E/R harness connector and ground.
      IPDM E/R Ground Continuity
      Connector Terminal
      E5 28 Not existed

    Is the inspection result normal?

    YES 

    GO TO STEP 6  .

    NO 

    Repair or replace harness or connector.

  4. CHECK IGNITION SWITCH OUTPUT SIGNAL (BCM)

    1. Disconnect push-button ignition switch connector.
    2. Check voltage between BCM harness connector and ground.
      (+) (-) Voltage (V)
      (Approx.)
      BCM
      Connector Terminal
      M122 89 Ground Battery voltage

    Is the inspection result normal?

    YES 

    GO TO STEP 5  .

    NO 

    Replace BCM. Refer to REMOVAL AND INSTALLATION .

  5. CHECK PUSH-BUTTON IGNITION SWITCH CIRCUIT (BCM)

    1. Disconnect BCM connector and IPDM E/R connector.
    2. Check continuity between BCM harness connector and push-button ignition switch harness connector.
      BCM Push-button ignition switch Continuity
      Connector Terminal Connector Terminal
      M122 89 M50 4 Existed
    3. Check continuity between BCM harness connector and ground.
      BCM Ground Continuity
      Connector Terminal
      M122 89 Not existed

    Is the inspection result normal?

    YES 

    GO TO STEP 6  .

    NO 

    Repair or replace harness or connector.

  6. CHECK INTERMITTENT INCIDENT

    Refer to INTERMITTENT INCIDENT .

    INSPECTION END

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