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Key Switch (Intelligent Key Unit Input) Check

  1. CHECK KEY SWITCH

    With CONSULT-III 

    Check key switch ("KEY SW") in "DATA MONITOR" mode with CONSULT-III.

    MONITOR ITEM CONDITION CHART

    Monitor item Condition
    KEY SW Insert mechanical key into ignition switch: ON
    Remove mechanical key from ignition switch: OFF

    Without CONSULT-III 

    1. Turn ignition switch OFF.
    2. Disconnect Intelligent Key unit harness connector.
    3. Check voltage between Intelligent Key unit harness connector M42 terminal 7 and ground.
      VOLTAGE SPECIFICATION

      Connector Terminals Condition Voltage (V) (Approx.)
      (+) (-)
      M42 7 Ground Insert mechanical key into ignition switch Battery voltage
      Remove mechanical key from ignition switch 0
      Fig 1: Checking Voltage Between Intelligent Key Unit Harness Connector M42 Terminal 7 And Ground
      G04916801Courtesy of NISSAN MOTOR CO., U.S.A.

      OK or NG 

      OK: Key switch is OK.

      NG: GO TO 2.

  2. CHECK KEY SWITCH POWER SUPPLY CIRCUIT
    1. Remove mechanical key from ignition switch.
    2. Disconnect key switch and ignition knob switch connector.
    3. Check voltage between key switch and ignition knob switch harness connector M49 terminal 2 and ground.

      2 - Ground : Battery voltage 

      OK or NG 

      OK: GO TO 3.

      NG: Repair or replace key switch and ignition knob switch power supply circuit.

      Fig 2: Checking Voltage Between Key Switch And Ignition Knob Switch Harness Connector M49 Terminal 2 And Ground
      G04927648Courtesy of NISSAN MOTOR CO., U.S.A.
  3. CHECK KEY SWITCH OPERATION

    Check continuity between key switch and ignition knob switch terminals 1 and 2.

    CONTINUITY CHART

    Component Terminals Condition Continuity
    Key switch 1 2 Insert mechanical key into ignition switch. Yes
    Remove mechanical key from ignition switch. No
    Fig 3: Checking Continuity Between Key Switch And Ignition Knob Switch Terminals 1 And 2
    G04916811Courtesy of NISSAN MOTOR CO., U.S.A.

    OK or NG 

    OK: GO TO 4.

    NG: Replace key cylinder assembly (built-in key switch).

  4. CHECK KEY SWITCH CIRCUIT
    1. Check continuity between Intelligent Key unit harness connector M42 (A) terminal 7 and key switch and ignition knob switch harness connector M49 (B) terminal 1.

      7 - 1 : Continuity should exist. 

    2. Check continuity between Intelligent Key unit harness connector M42 (A) terminal 7 and ground.

      7 - Ground : Continuity should not exist. 

      OK or NG 

      OK: Check the condition of harness and harness connector.

      NG: Repair or replace harness between Intelligent Key unit and key switch and ignition knob switch.

      Fig 4: Checking Continuity Between Intelligent Key Unit Connector M42 Terminal 7 And Key Switch And Ignition Knob Switch Connector M49 Terminal 1
      G04927650Courtesy of NISSAN MOTOR CO., U.S.A.
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