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Home >> Nissan-Datsun >> 2004 >> Sentra SE-R >> Repair and Diagnosis >> External Pages >> Different car >> Section 1748 (Body, Lock & Security System (Sedan)) >> Intelligent Key System >> Check Steering Lock Unit
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Check Steering Lock Unit

WARNING: This page is about a different car, the 2006 Infiniti G35. However, it is still accessible from the selected car via links, so may be relevant.
  1. CHECK STEERING LOCK UNIT POWER SUPPLY 
    1. Turn ignition switch OFF.
    2. Disconnect steering lock unit connector.
    3. Check voltage between steering lock unit harness connector M311 terminal 1 and ground.

      1 (Y) - Ground : Battery voltage 

      Fig 1: Identifying Voltage Between Steering Lock Unit Harness Connector M311 Terminal 1 And Ground
      G04122458Courtesy of NISSAN MOTOR CO., U.S.A.

    OK or NG

    • OK: GO TO 2.
    • NG: Repair or replace steering lock unit power supply circuit.
  2. CHECK STEERING LOCK UNIT GROUND CIRCUIT 

    Check continuity between steering lock unit harness connector M311 terminal 4 and ground.

    4 (G/R) - Ground : Continuity should exist. 

    Fig 2: Identifying Continuity Between Steering Lock Unit Harness Connector M311 Terminal 4 And Ground
    G04122459Courtesy of NISSAN MOTOR CO., U.S.A.

    OK or NG

    • OK: GO TO 3.
    • NG: GO TO 6.
  3. CHECK INTELLIGENT KEY UNIT OUTPUT SIGNAL 
    1. Connect steering lock unit connector.
    2. Check voltage between Intelligent Key unit harness connector M75 terminal 1 and ground.

      1 (L/Y) - Ground : Approx. 5V 

    Fig 3: Identifying Voltage Between Intelligent Key Unit Harness Connector M75 Terminal 1 And Ground
    G04122460Courtesy of NISSAN MOTOR CO., U.S.A.

    OK or NG

    • OK: GO TO 4.
    • NG: Replace Intelligent Key unit.
  4. CHECK STEERING LOCK COMMUNICATION SIGNAL 

    Check signal between Intelligent Key unit connector M75 terminal 32 and ground with oscilloscope.

    TERMINALS SIGNALS REFERENCE

    Connector Terminal (Wire color) Condition Signal (V) (Reference value)
    (+) (-)
    M75 32 (L/OR) Ground Ignition switch is pushed
    G04122461
    Fig 4: Identifying Signal Between Intelligent Key Unit Connector M75 Terminal 32 And Ground
    G04122462Courtesy of NISSAN MOTOR CO., U.S.A.

    OK or NG

    • OK: GO TO 5.
    • NG: Replace Intelligent Key unit.
  5. CHECK STEERING LOCK UNIT COMMUNICATION CIRCUIT 
    1. Disconnect Intelligent Key unit and steering lock unit connectors.
    2. Check continuity between Intelligent Key unit harness connector M75 terminals 1, 31, 32 and steering lock unit connector M311 terminals 2, 3, 4.

      (L/Y) - 2 (L/Y) : Continuity should exist. 

      31 (G/R) - 4 (G/R) : Continuity should exist. 

      32 (L/OR) - 3 (L/OR) : Continuity should exist. 

    3. Check continuity between steering lock unit harness connector M311 terminals 2, 3, 4 and ground.

    2 (L/Y) - Ground : Continuity should not exist. 

    3 (L/OR) - Ground : Continuity should not exist. 

    4 (G/R) - Ground : Continuity should not exist. 

    Fig 5: Identifying Continuity Between Steering Lock Unit Harness Connector M311 Terminals 2, 3, 4 And Ground
    G04122463Courtesy of NISSAN MOTOR CO., U.S.A.

    OK or NG

    • OK: Replace steering lock unit.
      • After replacing steering lock unit, perform registration procedure.
    • NG: Repair or replace harness between steering lock unit and Intelligent Key unit.
  6. CHECK STEERING LOCK UNIT COMMUNICATION CIRCUIT 
    1. Disconnect Intelligent Key unit connector.
    2. Check continuity between Intelligent Key unit harness connector M75 terminal 31 and steering lock unit connector M311 terminal 4.

      31 (G/R) - 4 (G/R) : Continuity should exist. 

    3. Check continuity between steering lock unit harness connector M311 terminal 4 and ground.

    4 (G/R) - Ground : Continuity should not exist. 

    Fig 6: Identifying Continuity Between Steering Lock Unit Harness Connector M311 Terminal 4 And Ground
    G04122464Courtesy of NISSAN MOTOR CO., U.S.A.

    OK or NG

    • OK: Replace Intelligent Key unit.
    • NG: Repair or replace harness between steering lock unit and Intelligent Key unit.