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Home >> Nissan-Datsun >> 2012 >> Quest SL >> Repair and Diagnosis >> Engine Performance >> System >> Engine Control System - Component Testing >> Cooling Fan >> Diagnosis Procedure
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Diagnosis Procedure

  1. CHECK COOLING FAN RELAY POWER SUPPLY
    1. Turn ignition switch OFF.
    2. Disconnect cooling fan relays-2, -3.
    3. Turn ignition switch ON.
    4. Check the voltage between cooling fan relays-2, -3 harness connectors and ground.
      Cooling fan relay Ground Voltage
      Connector Terminal
      E57 (cooling fan relay-2) 2 Ground Battery voltage
      5
      E59 (cooling fan relay-3) 2
      5

      Is the inspection result normal? 

      YES: GO TO 2.

      NO: Perform the trouble diagnosis for power supply circuit.

  2. CHECK COOLING FAN RELAY OUTPUT SIGNAL CIRCUIT
    1. Turn ignition switch OFF.
    2. Disconnect IPDM E/R harness connectors.
    3. Check the continuity between cooling fan relay-2, -3 harness connectors and IPDM E/R harness connector.
      Cooling fan relay IPDM E/R Continuity
      Connector Terminal Connector Terminal
      E57 (cooling fan relay-2) 1 E11 42 Existed
      E59 (cooling fan relay-3) 1 E10 34
    4. Also check harness for short to ground and short to power.

      Is the inspection result normal? 

      YES: GO TO 3.

      NO: Repair open circuit, short to ground or short to power in harness or connectors.

  3. CHECK COOLING FAN MOTOR POWER SUPPLY
    1. Disconnect cooling fan motor-1 harness connector.
    2. Check the voltage between cooling fan motor-1 harness connector and ground.
      Cooling fan motor-1 Ground Voltage
      Connector Terminal
      E301 1 Ground Battery voltage
      2

      Is the inspection result normal? 

      YES: GO TO 4.

      NO: Perform the trouble diagnosis for power supply circuit.

  4. CHECK COOLING FAN MOTOR CIRCUIT-I
    1. Disconnect cooling fan motor-2 harness connector.
    2. Check the continuity between cooling fan relay-2, -3 harness connectors and cooling fan motor-1, -2 harness connectors.
      Cooling fan relay Cooling fan motor Continuity
      Connector Terminal Connector Terminal
      E57 (cooling fan relay-2) 3 E302 (Cooling fan motor-2) 2 Existed
      7 E301 (Cooling fan motor-1) 3
      E59 (cooling fan relay-3) 3 E302 (Cooling fan motor-2) 1
      7 E301 (Cooling fan motor-1) 4
    3. Also check harness for short to ground and short to power.

      Is the inspection result normal? 

      YES: GO TO 5.

      NO: Perform the trouble diagnosis for power supply circuit.

  5. CHECK COOLING FAN MOTOR CIRCUIT-II
    1. Check the continuity between IPDM E/R harness connector and cooling fan motor-1, -2 harness connector.
      IPDM E/R Cooling fan motor Continuity
      Connector Terminal Connector Terminal
      E10 35 E301 (Cooling fan motor-1) 4 Existed
      38 E302 (Cooling fan motor-2) 1
    2. Also check harness for short to ground and short to power.

      Is the inspection result normal? 

      YES: GO TO 6.

      NO: Perform the trouble diagnosis for power supply circuit.

  6. CHECK COOLING FAN MOTOR CIRCUIT-III
    1. Check the continuity between cooling fan relay-2, -3 harness connectors and ground.
      Cooling fan motor Ground Continuity
      Connector Terminal
      E57 (cooling fan relay-2) 6 Ground Existed
      E59 (cooling fan relay-3) 6
    2. Also check harness for short to ground and short to power.

      Is the inspection result normal? 

      YES: GO TO 7.

      NO: Repair open circuit, short to ground or short to power in harness or connectors.

  7. CHECK COOLING FAN MOTOR CIRCUIT-IV
    1. Check the continuity between cooling fan motor-2 harness connector and ground.
      Cooling fan motor-2 Ground Continuity
      Connector Terminal
      E302 3 Ground Existed
      4
    2. Also check harness for short to ground and short to power.

      Is the inspection result normal? 

      YES: GO TO 8.

      NO: Repair open circuit, short to ground or short to power in harness or connectors.

  8. CHECK COOLING FAN RELAYS-2 AND -3

    Check cooling fan relays-2 and -3. Refer to "COMPONENT INSPECTION (COOLING FAN RELAY) ".

    Is the inspection result normal? 

    YES: GO TO 9.

    NO: Replace malfunctioning cooling fan relay.

  9. CHECK COOLING FAN MOTORS-1 AND -2

    Check cooling fan motors-1 and -2. Refer to "COMPONENT INSPECTION (COOLING FAN MOTOR) ".

    Is the inspection result normal? 

    YES: GO TO 10.

    NO: Replace malfunctioning cooling fan motor. Refer to "EXPLODED VIEW ".

  10. CHECK INTERMITTENT INCIDENT

    Check intermittent incident. Refer to "INTERMITTENT INCIDENT ".

    Is the inspection result normal? 

    YES: Replace IPDM E/R. Refer to "EXPLODED VIEW ".

    NO: Repair or replace error-detected parts.