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Home >> Nissan-Datsun >> 2010 >> Maxima S >> Repair and Diagnosis >> Engine Performance >> System >> Engine Control System - Component Testing >> Cooling Fan >> Diagnosis Procedure
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Diagnosis Procedure

Regarding Wiring Diagram information, refer to "WIRING DIAGRAM-ENGINE CONTROL SYSTEM- ".

  1. CHECK COOLING FAN RELAY POWER SUPPLY CIRCUIT
    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.
      CONNECTOR TERMINAL VOLTAGE CHART

      Cooling fan relay Ground Voltage
      Connector Terminal
      E42 (cooling fan relay-2) 2 Ground Battery voltage
      5
      E43 (cooling fan relay-3) 2
      5

      Is the inspection result normal? 

      YES: GO TO  3.

      NO: GO TO  2.

      Fig 1: Checking Voltage Between Cooling Fan Relays-2, -3 Harness Connectors And Ground
      G05867536Courtesy of NISSAN MOTOR CO., U.S.A.
  2. DETECT MALFUNCTIONING PART

    Check the following.

    • 10 A fuse (No. 33)
    • 40 A fusible link (letter K)
    • Joint connector-E01 E1
    • IPDM E/R harness connector E18
    • Junction block connectors E44, E48
    • Harness for open or short between cooling fan relay-2 and battery
    • Harness for open or short between cooling fan relay-3 and battery
    • Harness for open or short between cooling fan relay-2 and IPDM E/R
    • Harness for open or short between cooling fan relay-3 and IPDM E/R

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

  3. 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.
      CONNECTOR TERMINAL CONTINUITY CHART

      Cooling fan relay IPDM E/R Continuity
      Connector Terminal Connector Terminal
      E42 (cooling fan relay-2) 1 E17 42 Existed
      E43 (cooling fan relay-3) 1 E18 34
    4. Also check harness for short to ground and short to power.

      Is the inspection result normal? 

      YES: GO TO  5.

      NO: GO TO  4.

  4. DETECT MALFUNCTIONING PART

    Check the following.

    • Junction block connectors E47, E48
    • Harness for open or short between cooling fan relay-2 and IPDM E/R
    • Harness for open or short between cooling fan relay-3 and IPDM E/R

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

  5. CHECK COOLING FAN MOTOR POWER SUPPLY CIRCUIT
    1. Disconnect cooling fan motor-1 harness connector.
    2. Check the voltage between cooling fan motor-1 harness connector and ground.
      CONNECTOR TERMINAL VOLTAGE CHART

      Cooling fan motor-1 Ground Voltage
      Connector Terminal
      E220 1 Ground Battery voltage
      2

      Is the inspection result normal? 

      YES: GO TO  7.

      NO: GO TO  6.

      Fig 2: Checking Voltage Between Cooling Fan Motor-1 Harness Connector And Ground
      G04905696Courtesy of NISSAN MOTOR CO., U.S.A.
  6. DETECT MALFUNCTIONING PART

    Check the following.

    • 40 A fusible link (letter M)
    • Harness connector E12, E203
    • Harness for open or short between cooling fan motor-1 and battery

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

  7. 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.
      CONNECTOR TERMINAL CONTINUITY CHART

      Cooling fan relay Cooling fan motor Continuity
      Connector Terminal Connector Terminal
      E42 (cooling fan relay-2) 3 E221 (Cooling fan motor-2) 2 Existed
      7 E220 (Cooling fan motor-1) 3
      E43 (cooling fan relay-3) 3 E221 (Cooling fan motor-2) 1
      7 E220 (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  9.

      NO: GO TO  8.

  8. DETECT MALFUNCTIONING PART

    Check the following.

    • Joint connector-E02 E20
    • Harness connector E12, E203
    • Harness for open or short between cooling fan motor-1 and cooling fan relay-2
    • Harness for open or short between cooling fan motor-1 and cooling fan relay-3
    • Harness for open or short between cooling fan motor-2 and cooling fan relay-2
    • Harness for open or short between cooling fan motor-2 and cooling fan relay-3

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

  9. CHECK COOLING FAN MOTOR CIRCUIT-II
    1. Check the continuity between IPDM E/R harness connector and cooling fan motor-1, -2 harness connector.
      CONNECTOR TERMINAL CONTINUITY CHART

      IPDM E/R Cooling fan motor Continuity
      Connector Terminal Connector Terminal
      E18 35 E220 (Cooling fan motor-1) 4 Existed
      38 E221 (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  11.

      NO: GO TO  10.

  10. DETECT MALFUNCTIONING PART

    Check the following.

    • Joint connector-E02 E20
    • Harness connector E70, E305
    • Harness for open or short between cooling fan motor-1 and IPDM E/R
    • Harness for open or short between cooling fan motor-2 and IPDM E/R

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

  11. CHECK COOLING FAN MOTOR CIRCUIT-III
    1. Check the continuity between cooling fan relay-2, -3 harness connectors and ground.
      CONNECTOR TERMINAL CONTINUITY CHART

      Cooling fan motor Ground Continuity
      Connector Terminal
      E42 (cooling fan relay-2) 6 Ground Existed
      E43 (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  12.

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

  12. CHECK COOLING FAN MOTOR CIRCUIT-IV
    1. Check the continuity between cooling fan motor-2 harness connector and ground.
      CONNECTOR TERMINAL CONTINUITY CHART

      Cooling fan motor-2 Ground Continuity
      Connector Terminal
      E221 3 Ground Existed
      4
    2. Also check harness for short to ground and short to power.

      Is the inspection result normal? 

      YES: GO TO  13.

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

  13. CHECK COOLING FAN RELAYS-2 AND -3

    Refer to "COMPONENT INSPECTION (COOLING FAN RELAY) ".

    Is the inspection result normal? 

    YES: GO TO  14.

    NO: Replace malfunctioning cooling fan relay.

  14. CHECK COOLING FAN MOTORS-1 AND -2

    Refer to "COMPONENT INSPECTION (COOLING FAN MOTOR) ".

    Is the inspection result normal? 

    YES: GO TO  15.

    NO: Replace malfunctioning cooling fan motor.

  15. CHECK INTERMITTENT INCIDENT

    Perform INTERMITTENT INCIDENT .

    Is the inspection result normal? 

    YES: Replace IPDM E/R.

    NO: Repair or replace harness connectors.

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