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Diagnosis Procedure

  1. CHECK POWER SUPPLY CIRCUIT
    1. Turn ignition switch OFF.
    2. Disconnect IPDM E/R harness connector E120.
    3. Check voltage between IPDM E/R terminal 22 and ground with CONSULT-III or tester.

      Voltage: Battery voltage 

    OK or NG 

    OK: GO TO  3.

    NG: GO TO 2.

    Fig 1: Checking Voltage Between IPDM E/R Terminal 22 And Ground
    G05739714Courtesy of NISSAN MOTOR CO., U.S.A.
  2. DETECT MALFUNCTIONING PART

    Check the following.

    • 40A fusible link
    • Harness for open or short between IPDM E/R and battery

      Repair open circuit or short to ground or short to power in harness or connectors.

  3. CHECK COOLING FAN MOTOR CIRCUIT FOR OPEN OR SHORT
    1. Disconnect cooling fan motor harness connector (1).
    2. Check harness continuity between cooling fan motor terminal 2 and IPDM E/R terminal 24, cooling fan motor terminal 1 and ground.

      Refer to WIRING DIAGRAM .

      Continuity should exist. 

    3. Also check harness for short to ground and short to power.

    OK or NG 

    OK: GO TO 4.

    NG: Repair open circuit or short to ground or short to power in harness or connectors.

    Fig 2: Identifying Cooling Fan Motor Harness Connector
    G05739715Courtesy of NISSAN MOTOR CO., U.S.A.
  4. CHECK COOLING FAN MOTOR

    Refer to "COMPONENT INSPECTION ".

    OK or NG 

    OK: GO TO 5.

    NG: Replace cooling fan motor.

  5. CHECK INTERMITTENT INCIDENT

    Perform "HOW TO CHECK TERMINAL " and "INTERMITTENT INCIDENT ".

    OK or NG 

    OK: Replace IPDM E/R. Refer to "REMOVAL AND INSTALLATION OF IPDM E/R ".

    NG: Repair or replace harness connectors.