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Home >> Infiniti >> 2012 >> G37 Base, 2D Convertible >> Repair and Diagnosis >> External Pages >> Different variant/trim >> Section 33 (Security Control System (Coupe)) >> DTC/Circuit Diagnosis >> DTC B2556: Push-Button Ignition Switch >> Diagnosis Procedure
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Diagnosis Procedure

WARNING: This page is about a different variant/trim than selected.
  1. CHECK PUSH-BUTTON IGNITION SWITCH INPUT SIGNAL
    1. Turn ignition switch OFF.
    2. Disconnect push-button ignition switch connector.
    3. Check voltage between push-button ignition switch harness connector and ground.
      (+) (-) Voltage (V) (Approx.)
      Push-button ignition switch
      Connector Terminal
      M50 4 Ground Battery voltage

      Is the inspection result normal? 

      YES: GO TO  3.

      NO: GO TO 2.

  2. CHECK PUSH-BUTTON IGNITION SWITCH CIRCUIT
    1. Disconnect BCM connector and IPDM E/R connector.
    2. Check continuity between push-button ignition switch harness connector and BCM harness connector.
      Push-button ignition switch BCM Continuity
      Connector Terminal Connector Terminal
      M50 4 M121 (Models without steering lock unit) 60 Existed
      M122 (Models with steering lock unit) 89
    3. Check continuity between push-button ignition switch harness connector and ground.
      Push-button ignition switch Ground Continuity
      Connector Terminal
      M50 4 Not existed

      Is the inspection result normal? 

      YES: Replace BCM. Refer to "REMOVAL AND INSTALLATION ".

      NO: Repair or replace harness.

  3. CHECK PUSH-BUTTON IGNITION SWITCH GROUND CIRCUIT

    Check continuity between push-button ignition switch harness connector and ground.

    Push-button ignition switch Ground Continuity
    Connector Terminal
    M50 1 Existed

    Is the inspection result normal? 

    YES: GO TO 4.

    NO: Repair or replace harness.

  4. CHECK PUSH-BUTTON IGNITION SWITCH

    Refer to "COMPONENT INSPECTION ".

    Is the inspection result normal? 

    YES: GO TO 5.

    NO: Replace push-button ignition switch. Refer to "REMOVAL AND INSTALLATION ".

  5. CHECK INTERMITTENT INCIDENT

    Refer to "INTERMITTENT INCIDENT ".

    : INSPECTION END