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Home >> Infiniti >> 2022 >> QX80 Premium Select, AWD >> Repair and Diagnosis >> Engine Performance >> Engine Control Systems >> Engine Control System (Diagnostics) (1 Of 2) >> Component/Circuit Diagnosis >> Electrically-Controlled Cooling Fan Coupling >> Diagnosis Procedure
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Diagnosis Procedure

  1. CHECK DRIVE BELT 
    1. Turn ignition switch OFF.
    2. Check that the drive belt is not broken.

    Is inspection result normal?

    YES

    GO TO 2.

    NO

    Replace drive belt.

  2. CHECK ELECTRICALLY-CONTROLLED COOLING FAN COUPLING POWER SUPPLY 
    1. Disconnect electrically-controlled cooling fan coupling harness connector.
    2. Turn ignition switch ON.
    3. Check the voltage between electrically-controlled cooling fan coupling harness connector and ground.

      +

      -

      Voltage

      (Approx.)

      Electrically-controlled cooling fan coupling

      Connector

      Terminal

      F39

      1

      Ground

      Battery voltage

    Is inspection result normal?

    YES

    GO TO 3.

    NO

    Perform trouble diagnosis for power supply circuit.

  3. CHECK ELECTRICALLY-CONTROLLED COOLING FAN COUPLING GROUND CIRCUIT 
    1. Turn ignition switch OFF.
    2. Check the continuity between electrically-controlled cooling fan coupling harness connector and ground.

      +

      -

      Continuity

      Electrically-controlled cooling fan coupling

      Connector

      Terminal

      F39

      6

      Ground

      Existed

    Is inspection result normal?

    YES

    GO TO 4.

    NO

    Repair or replace error-detected parts.

  4. CHECK ELECTRICALLY-CONTROLLED COOLING FAN COUPLING CONTROL SIGNAL 

    SYMBOL WITH CONSULT

    1. Start the engine.
    2. Perform "FAN DUTY CONTROL" in "ACTIVE TEST" mode of "ECM" with CONSULT.
    3. Set the Duty value to 100%.
    4. Check the voltage between electrically-controlled cooling fan coupling harness connector and ground.
      CAUTION: Wait for 1 minute or more to measure.

      +

      -

      Voltage

      (Approx.)

      Electrically-controlled cooling fan coupling

      Connector

      Terminal

      F39

      3

      Ground

      5 V

    SYMBOL WITHOUT CONSULT

    1. Start the engine and warm up the engine until engine coolant temperature reaches at least 98 Deg. C (209 Deg. F).
    2. Check the voltage between electrically-controlled cooling fan coupling harness connector and ground.
      CAUTION: Wait for 1 minute or more to measure.

      +

      -

      Voltage

      (Approx.)

      Electrically-controlled cooling fan coupling

      Connector

      Terminal

      F39

      3

      Ground

      5 V

    Is the inspection result normal?

    YES

    GO TO 7.

    NO

    GO TO 5.

  5. CHECK ELECTRICALLY-CONTROLLED COOLING FAN COUPLING CONTROL CIRCUIT 
    1. Turn ignition switch OFF.
    2. Disconnect IPDM E/R harness connector.
    3. Check the continuity between electrically-controlled cooling fan coupling harness connector and IPDM E/R harness connector.

      +

      -

      Continuity

      Electrically-controlled cooling fan coupling

      IPDM E/R

      Connector

      Terminal

      Connector

      Terminal

      F39

      3

      E17

      72

      Existed

    4. Also check harness for short to power.

    Is the inspection result normal?

    YES

    GO TO 6.

    NO

    Repair or replace error-detected parts.

  6. CHECK CAN COMMUNICATION 

    Refer to Trouble Diagnosis Flow Chart .

    Is inspection result normal?

    YES

    Check intermittent incident. Refer to Inspection .

    NO

    Repair or Replace error-detected parts.

  7. CHECK COOLING FAN SPEED SENSOR 

    Refer to DTC Diagnosis Procedure .

    Is inspection result normal?

    YES

    Replace electrically-controlled cooling fan coupling. Refer to ENGINE COOLING FAN : Removal & Installation .

    NO

    Repair or replace error-detected parts.