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Home >> Infiniti >> 2008 >> G37 Base >> Repair and Diagnosis >> Steering >> Manual Steering >> Steering Control System (With 4WAS) >> Component Diagnosis >> Power Supply And Ground Circuit >> Diagnosis Procedure (4WAS Front Control Unit)
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Diagnosis Procedure (4WAS Front Control Unit)

  1. CHECK 4WAS FRONT CONTROL UNIT POWER SUPPLY
    1. Turn the ignition switch OFF.
    2. Disconnect 4WAS front control unit harness connector.
    3. Check the voltage between 4WAS front control unit harness connectors and the ground.
      VOLTAGE REFERENCE CHART

      4WAS front control unit Voltage (Approx.)
      Connector Terminal
      M41 11 - Ground Battery voltage
      M42 15 - Ground 0 V
    4. Turn the ignition switch ON.
      CAUTION: Never start the engine.
    5. Check the voltage between 4WAS front control unit harness connectors and the ground.
    VOLTAGE REFERENCE CHART

    4WAS front control unit Voltage (Approx.)
    Connector Terminal
    M41 11 - Ground Battery voltage
    M42 15 - Ground

    Is the inspection result normal? 

    YES: GO TO  2.

    NO: Check the following items. Repair or replace the malfunctioning parts.

    • 40A fusible link (#I) open
    • Short among 40A fusible link (#I) connector, 4WAS front control unit harness connector No. 11 terminal and the ground
    • Open between the battery and 4WAS front control unit harness connector No. 11 terminal
    • 10A fuse (#3) open
    • Short among 10A fuse (#3) connector, 4WAS front control unit harness connector No. 15 terminal and the ground
    • Short among 10A fuse (#3) connector, unified meter and A/C amp No. 53 terminal and the ground
    • Open between the ignition switch and 4WAS front control unit harness connector No. 15 terminal
    • Battery or ignition switch
  2. CHECK 4WAS FRONT CONTROL UNIT GROUND

    Check the continuity between 4WAS front control unit harness connector and the ground.

    CONTINUITY REFERENCE CHART

    4WAS front control unit Continuity
    Connector Terminal
    M41 12 - Ground Existed
    M42 18 - Ground
    34 - Ground

    Is the inspection result normal? 

    YES: INSPECTION END

    NO: Repair or replace the harnesses and connectors.