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Key Switch Signal Inspection (Without Intelligent Key)

  1. CHECK FUSE

    Check if the key switch 10A fuse [No. 19, located in the fuse block (J/B)] is blown.

    OK or NG 

    OK: GO TO 2.

    NG: Be sure to repair the cause of malfunction before installing new fuse. Refer to POWER SUPPLY ROUTING CIRCUIT .

  2. CHECK BCM INPUT SIGNAL

    With CONSULT-III 

    1. Select "BCM".
    2. With "DATA MONITOR" of "BUZZER", confirm "KEY ON SW" when the key is operated.

      "KEY ON SW" 

      When key is inserted into ignition key cylinder : ON 

      When key is removed from ignition key cylinder : OFF 

      Without CONSULT-III 

      Check voltage between BCM harness connector and ground.

      TERMINAL VOLTAGE REFERENCE

      Terminals Condition Voltage (Approx.)
      (+) (-)
      BCM connector Terminal
      M18 37 Ground Key is inserted Battery voltage
      Key is removed 0 V
      Fig 1: Checking Voltage Between BCM Harness Connector And Ground
      G04928459Courtesy of NISSAN MOTOR CO., U.S.A.

      OK or NG 

      OK: Key switch signal is OK. Return to "TROUBLE DIAGNOSIS ".

      NG: GO TO 3.

  3. CHECK KEY SWITCH
    1. Turn ignition switch OFF.
    2. Disconnect key switch connector.
    3. Check continuity between key switch terminals 1 and 2.
      TERMINAL CONTINUITY REFERENCE

      Terminals Condition Continuity
      1 2 When key is inserted into ignition key cylinder Yes
      When key is removed from ignition key cylinder No
      Fig 2: Checking Continuity Between Key Switch Terminals 1 And 2
      G04928460Courtesy of NISSAN MOTOR CO., U.S.A.

      OK or NG 

      OK: GO TO 4.

      NG: Replace key switch.

  4. CHECK KEY SWITCH CIRCUIT
    1. Disconnect BCM connector.
    2. Check continuity between BCM harness connector (A) and key switch harness connector (B).
      TERMINAL CONTINUITY REFERENCE

      A B Continuity
      Connector Terminal Connector Terminal
      M18 37 M50 1 Yes
      Fig 3: Checking Continuity Between BCM And Key Switch Harness Connector Terminals
      G04928461Courtesy of NISSAN MOTOR CO., U.S.A.
    3. Check continuity between BCM harness connector (A) and ground.
      TERMINAL CONTINUITY REFERENCE

      A Ground Continuity
      Connector Terminal
      M18 37 No

      OK or NG 

      OK: GO TO 5.

      NG: Repair harness or connector.

  5. CHECK KEY SWITCH POWER SUPPLY CIRCUIT

    Check voltage between key switch harness connector and ground.

    TERMINAL VOLTAGE REFERENCE

    Terminals Voltage (Approx.)
    (+) (-)
    Key switch connector Terminal
    M50 2 Ground Battery voltage
    Fig 4: Checking Voltage Between Key Switch Harness Connector And Ground
    G04928462Courtesy of NISSAN MOTOR CO., U.S.A.

    OK or NG 

    OK: Replace BCM. Refer to "REMOVAL AND INSTALLATION OF BCM ".

    NG: Repair harness or connector.