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Diagnostic Procedure

  1. CHECK STEERING LOCK SIGNAL

    Check voltage between power distribution unit connector and ground.

    VOLTAGE REFERENCE CHART

    Terminals Condition Voltage (V) (Approx.)
    (+) (-)
    Power distribution unit connector Terminal
    M30 6 Ground When turn ignition switch to START with Intelligent Key in the car Battery voltage
    7
    6 When turn ignition switch to OFF (steering lock operates) Battery voltage
    ↓
    0
    ↓
    Battery voltage
    7
    Fig 1: Checking Voltage Between Power Distribution Unit Connector And Ground
    G05212319Courtesy of NISSAN MOTOR CO., U.S.A.

    OK or NG 

    OK: GO TO  2.

    NG: GO TO  4.

  2. CHECK POWER DISTRIBUTION UNIT POWER SUPPLY

    Check voltage between power distribution unit connector and ground.

    VOLTAGE REFERENCE CHART

    Terminals Condition Voltage (V) (Approx.)
    (+) (-)
    Power distribution unit connector Terminal
    M30 3 Ground When turn ignition switch to OFF (steering lock operates) Battery voltage
    ↓
    0
    ↓
    Battery voltage
    Ignition switch OFF 0
    Fig 2: Checking Voltage Between Power Distribution Unit Connector And Ground
    G05212320Courtesy of NISSAN MOTOR CO., U.S.A.

    OK or NG 

    OK: GO TO  3.

    NG: Check if "B2558 PDU" is displayed on self-diagnosis results. If it is displayed, first perform the diagnosis.

  3. CHECK POWER SUPPLY CIRCUIT
    1. Turn ignition switch OFF.
    2. Disconnect power distribution unit and steering lock unit connector.
    3. Check continuity between power distribution unit connector and steering lock unit connector.
      CONTINUITY REFERENCE CHART

      A B Continuity
      Power distribution unit connector Terminal Steering lock unit connector Terminal
      M30 3 M35 1 Yes
    4. Check continuity between power distribution unit connector and ground.
    Fig 3: Checking Continuity Between Power Distribution Unit And Steering Lock Unit Connector
    G05212321Courtesy of NISSAN MOTOR CO., U.S.A.
    CONTINUITY REFERENCE CHART

    A Ground Continuity
    Power distribution unit connector Terminal
    M30 3 No

    OK or NG 

    OK: GO TO  5.

    NG: Repair or replace harness.

  4. CHECK COMMUNICATION CIRCUIT 1
    1. Turn ignition switch OFF.
    2. Disconnect Intelligent Key unit and power distribution unit connector.
    3. Check continuity between Intelligent Key unit connector and power distribution unit connector.
      CONTINUITY REFERENCE CHART

      A B Continuity
      Intelligent Key unit connector Terminal Power distribution unit connector Terminal
      M33 46 M30 6 Yes
      71 7
    4. Check continuity between Intelligent Key unit connector and ground.
    CONTINUITY REFERENCE CHART

    A Ground Continuity
    Intelligent Key unit connector Terminal
    M33 46 No
    71
    Fig 4: Checking Continuity Between Intelligent Key Unit And Power Distribution Unit Connector
    G05212322Courtesy of NISSAN MOTOR CO., U.S.A.

    OK or NG 

    OK: Check the condition of harness and connector.

    NG: Repair or replace harness.

  5. CHECK SIGNAL CIRCUIT
    1. Connect steering lock unit and power distribution unit connector.
    2. Check continuity between steering lock unit connector and ground.
    CONTINUITY REFERENCE CHART

    Terminals Condition Voltage (V) (Approx.)
    (+) (-)
    Steering lock unit connector Terminal
    M35 3 Ground When turn ignition switch to START with Intelligent Key in the car Battery voltage
    8 0
    3 Ignition switch: OFF 0
    8 Battery voltage
    Fig 5: Checking Continuity Between Steering Lock Unit Connector And Ground
    G05212323Courtesy of NISSAN MOTOR CO., U.S.A.

    OK or NG 

    OK: Replace steering lock unit.

    NG: GO TO  6.

  6. CHECK COMMUNICATION CIRCUIT 2
    1. Turn ignition switch OFF.
    2. Disconnect Intelligent Key unit and steering lock unit connector.
    3. Check continuity between Intelligent Key unit connector and steering lock unit connector.
      CONTINUITY REFERENCE CHART

      A B Continuity
      Intelligent Key unit connector Terminal Steering lock unit connector Terminal
      M33 69 M35 3 Yes
      70 8
    4. Check continuity between Intelligent Key unit connector and ground.
    Fig 6: Checking Continuity Between Intelligent Key Unit And Steering Lock Unit Connector
    G05212324Courtesy of NISSAN MOTOR CO., U.S.A.
    CONTINUITY REFERENCE CHART

    A Ground Continuity
    Intelligent Key unit connector Terminal
    M33 69 No
    70

    OK or NG 

    OK: Check the condition of harness and connector. If it is OK, check the self-diagnosis results using CONSULT-III again.

    NG: Repair or replace harness.

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