Diagnosis Procedure

With CONSULT-III 

1. Turn ignition switch ON.
2. Perform "FAN DUTY CONTROL" in "ACTIVE TEST" mode with CONSULT-III.
3. Check that cooling fan speed varies according to the percent.

Without CONSULT-III 

1. Perform IPDM E/R auto active test and check cooling fan motors operation, refer to "AUTO ACTIVE TEST ".
2. Check that cooling fan operates.

OK or NG 

OK: GO TO 2.

NG: GO TO  6.

Apply pressure to the cooling system with a tester, and check if the pressure drops.

Testing pressure: 157 kPa (1.6 kg/cm ²  , 23 psi) 

Pressure should not drop  .

OK or NG 

OK: GO TO 3.

NG: Check the following for leakage. Refer to "INSPECTION ".

• Hose
• Radiator
• Water pump

Fig 1: Checking Cooling System For Leak

Courtesy of NISSAN MOTOR CO., U.S.A.

Apply pressure to cap with a tester.

Radiator cap relief pressure: 59 - 98 kPa (0.6 - 1.0 kg/cm ²  , 9 - 14 psi) 

OK or NG 

OK: GO TO 4.

NG: Replace radiator cap.

Fig 2: Applying Pressure To Cap With Tester

Courtesy of NISSAN MOTOR CO., U.S.A.

Check the following.

• Thermostat. (Refer to "REMOVAL AND INSTALLATION ".)
• Water control valve. (Refer to "REMOVAL AND INSTALLATION ".)
• Engine coolant temperature sensor. (Refer to "COMPONENT INSPECTION ".)

OK or NG 

OK: GO TO 5.

NG: Replace malfunctioning component.

If the cause cannot be isolated, go to "MAIN 13 CAUSES OF OVERHEATING ".

INSPECTION END 

1. Turn ignition switch OFF.
2. Disconnect cooling fan control module (1) harness connector E42.
   • Vehicle Front
   • Colling fan motor-2 (2)
   • Colling fan motor-1 (3)
   Fig 3: Identifying Cooling Fan Control Module Harness Connector E42

   Courtesy of NISSAN MOTOR CO., U.S.A.
3. Turn ignition switch ON.
4. Check voltage between cooling fan control module terminal 3 and ground with CONSULT-III or tester.

Voltage: Battery voltage 

OK or NG 

OK: GO TO 7.

NG: GO TO  12.

Fig 4: Checking Voltage Between Cooling Fan Control Module Terminal 3 And Ground

Courtesy of NISSAN MOTOR CO., U.S.A.

1. Turn ignition switch OFF.
2. Check harness continuity between cooling fan control module terminal 1 and ground.

   Refer to SYSTEM WIRING DIAGRAMS article.

   Continuity should exist  .

3. Also check harness for short to power.

OK or NG 

OK: GO TO 8.

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

1. Disconnect IPDM E/R harness connector E8, E9.
2. Check harness continuity between IPDM E/R terminal 38, 51 and ground.

   Refer to SYSTEM WIRING DIAGRAMS article.

   Continuity should exist  .

3. Also check harness for short to power.

OK or NG 

OK: GO TO 9.

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

1. Check harness continuity between IPDM E/R terminal 59 and cooling fan control module terminal 2.

   Refer to SYSTEM WIRING DIAGRAMS article.

   Continuity should exist  .

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

OK or NG 

OK: GO TO 10.

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

1. Reconnect all harness connectors disconnected.
2. Disconnect cooling fan control module harness connectors E301, E303.
3. Turn ignition switch ON.
4. Check voltage between cooling fan control module terminals 4, 6 and ground with CONSULT-III or tester.

Voltage: Battery voltage 

OK or NG 

OK: GO TO 11.

NG: Replace cooling fan control module.

Fig 5: Checking Voltage Between Cooling Fan Control Module Terminals 4, 6 And Ground

Courtesy of NISSAN MOTOR CO., U.S.A.

Refer to "COMPONENT INSPECTION ".

OK or NG 

OK: GO TO  16.

NG: Replace cooling fan motor.

1. Turn ignition switch OFF.
2. Disconnect cooling fan relay.
3. Turn ignition switch ON.
4. Check voltage between cooling fan relay terminals 1, 3 and ground with CONSULT-III or tester.

Voltage: Battery voltage 

OK or NG 

OK: GO TO  14.

NG: GO TO 13.

Fig 6: Checking Voltage Between Cooling Fan Relay Terminals 1, 3 And Ground

Courtesy of NISSAN MOTOR CO., U.S.A.

Check the following.

• 10 A fuse
• Fuse block (J/B) connector E102
• 50 A fusible link
• Harness for open or short between cooling fan relay and fuse
• Harness for open or short between cooling fan relay and battery

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

1. Turn ignition switch OFF.
2. Disconnect IPDM E/R harness connector E9.
3. Check harness continuity between the following;

   Cooling fan relay terminal 2 and IPDM E/R terminal 56,

   Cooling fan relay terminal 5 and cooling fan control module terminal 3.

   Refer to SYSTEM WIRING DIAGRAMS article.

   Continuity should exist  .

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

OK or NG 

OK: GO TO 15.

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

Refer to "COMPONENT INSPECTION ".

OK or NG 

OK: GO TO 16.

NG: Replace cooling fan relay.

Perform "DIAGNOSIS PROCEDURE ".

OK or NG 

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

NG: Repair or replace harness connectors.