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Diagnostic Test

  1. PERFORM ECM SELF-DIAGNOSIS

    G-20With CONSULT 

    1. Turn the ignition switch ON.

    Perform "ENGINE" self-diagnosis. Refer to CONSULT FUNCTION .

    Is any DTC detected?

    YES 

    Check the DTC.

    NO 

    GO TO STEP 2. 

  2. CHECK HARNESS BETWEEN ECM AND POWER STEERING CONTROL UNIT

    1. Turn the ignition switch OFF.
    2. Disconnect ECM harness connectors.
    3. Disconnect power steering control unit harness connector.
    4. Check continuity between ECM harness connector and power steering control unit harness connector.
      ECM Power steering control unit Continuity
      Connector Terminal Connector Terminal
      M107 110 M108 10 Existed
    5. Check continuity between power steering control unit harness connector and ground.
      Power steering control unit - Continuity
      Connector Terminal
      M108 10 Ground Not existed

    Is the inspection result normal?

    YES 

    GO TO STEP 3. 

    NO 

    Repair or replace damaged parts.

  3. CHECK ENGINE SPEED SIGNAL (1)

    1. Connect ECM harness connectors.
    2. Check signal between ECM harness connector and ground with oscilloscope.
      ECM - Condition Voltage (Approx.)
      Connector Terminal
      M107 110 Ground Engine is running
      • Warm-up condition
      • Idle speed
      GNSJMBIA0076GB-076Courtesy of NISSAN NORTH AMERICA, INC.
      Engine is running
      • Warm-up condition
      • Engine speed: Approx. 2, 000 RPM
      GNSJMBIA0077GB-077Courtesy of NISSAN NORTH AMERICA, INC.

    Is the inspection result normal?

    YES 

    GO TO STEP 4. 

    NO 

    Replace ECM. Refer to DESCRIPTION .

  4. CHECK ENGINE SPEED SIGNAL (2)

    1. Turn the ignition switch OFF.
    2. Connect power steering control unit harness connector.
    3. Check signal between power steering control unit harness connector and ground with oscilloscope.
      Power steering control unit - Condition Voltage (Approx.)
      Connector Terminal
      M108 10 Ground Engine is running
      • Warm-up condition
      • Idle speed
      GNSJMBIA0076GB-076Courtesy of NISSAN NORTH AMERICA, INC.
      Engine is running
      • Warm-up condition
      • Engine speed: Approx. 2, 000 RPM
      GNSJMBIA0077GB-077Courtesy of NISSAN NORTH AMERICA, INC.

    Is the inspection result normal?

    YES 

    GO TO STEP 5. 

    NO 

    Replace power steering control unit. Refer to EXPLODED VIEW WITH TORQUE SPECIFICATIONS .

  5. CHECK TERMINALS AND HARNESS CONNECTORS

    • Check power steering control unit pin terminals for damage or loose connection with harness connector.
    • Check ECM pin terminals for damage or loose connection with harness connector.

    Is the inspection result normal?

    YES 

    INSPECTION END

    NO 

    Repair or replace damaged parts.

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