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Key Switch Signal Inspection (Without Intelligent Key)

WARNING: This page is about a different car, the 2010 Nissan Sentra. However, it is still accessible from the selected car via links, so may be relevant.
  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.

    CONNECTOR TERMINAL VOLTAGE CHART

    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 Terminal 37 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.
      CONNECTOR TERMINAL CONTINUITY CHART

      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).
      CONNECTOR TERMINAL CONTINUITY CHART

      A B Continuity
      Connector Terminal Connector Terminal
      M18 37 M50 1 Yes
    3. Check continuity between BCM harness connector (A) and ground.
      CONNECTOR TERMINAL CONTINUITY CHART

      A Ground Continuity
      Connector Terminal
      M18 37 No
      Fig 3: Checking Continuity Between BCM Harness Connector And Key Switch Harness Connector
      G04928461Courtesy of NISSAN MOTOR CO., U.S.A.

      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.

    CONNECTOR TERMINAL VOLTAGE CHART

    Terminals Voltage (Approx.)
    (+) (-)
    Key switch connector Terminal
    M50 2 Ground Battery voltage

    OK or NG 

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

    NG: Repair harness or connector.

    Fig 4: Checking Voltage Between Key Switch Harness Connector And Ground
    G04928462Courtesy of NISSAN MOTOR CO., U.S.A.
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