Diagnostic Procedure

CHECK COOLING FAN OPERATION
With CONSULT-III
1. Turn ignition switch ON.
2. Perform "FAN DUTY CONTROL" in "ACTIVE TEST" mode with CONSULT-III.
3. Make sure 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. Make sure that cooling fan operates.
OK or NG

OK: GO TO 2.

NG: GO TO 6.
CHECK COOLING SYSTEM FOR LEAK
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)

CAUTION: Higher than the specified pressure may cause radiator damage. Pressure should not drop.

OK or NG

OK: GO TO 3.

NG: Check the following for leak. Refer to "LEAK CHECK ".
- Hose
- Radiator
- Water pump
Fig 1: Applying Pressure To Cooling System With Tester
Courtesy of NISSAN MOTOR CO., U.S.A.
CHECK RADIATOR CAP
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 THERMOSTAT
Check the following.
- Thermostat. (Refer to "THERMOSTAT AND WATER CONTROL VALVE ".)
- Water control valve. (Refer to "THERMOSTAT AND WATER CONTROL VALVE ".)
- Engine coolant temperature sensor. (Refer to "COMPONENT INSPECTION ".)
OK or NG

OK: GO TO 5.

NG: Replace malfunctioning component.
CHECK MAIN 13 CAUSES
If the cause cannot be isolated, go to "MAIN 13 CAUSES OF OVERHEATING ".

>> INSPECTION END
CHECK COOLING FAN CONTROL MODULE POWER SUPPLY CIRCUIT-I
1. Turn ignition switch OFF.
2. Disconnect cooling fan control module (1) harness connector E42.
  - <=: Vehicle front
  - Cooling fan motor-2 (2)
  - Cooling fan motor-1 (3)
3. Turn ignition switch ON.
  
  Fig 3: Identifying Cooling Fan Control Module And Cooling Fan Motor
  Courtesy of NISSAN MOTOR CO., U.S.A.
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.
CHECK COOLING FAN CONTROL MODULE GROUND CIRCUIT
1. Turn ignition switch OFF.
2. Check harness continuity between cooling fan control module terminal 1 and ground.
  Refer to WIRING DIAGRAM .
  
  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.
CHECK IPDM E/R GROUND CIRCUIT
1. Disconnect IPDM E/R harness connector E8, E9.
2. Check harness continuity between IPDM E/R terminal 38, 51 and ground.
  Refer to WIRING DIAGRAM .
  
  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.
CHECK COOLING FAN CONTROL SIGNAL CIRCUIT
1. Check harness continuity between IPDM E/R terminal 59 and cooling fan control module terminal 2.
  Refer to WIRING DIAGRAM .
  
  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.
CHECK COOLING FAN CONTROL MODULE OUTPUT SIGNAL CIRCUIT
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.
CHECK COOLING FAN MOTORS -1 AND -2
Refer to "COMPONENT INSPECTION ".

OK or NG

OK: GO TO 16.

NG: Replace cooling fan motor.
CHECK COOLING FAN CONTROL MODULE POWER SUPPLY CIRCUIT-II
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.
DETECT MALFUNCTIONING PART
Check the following.
- 10A fuse
- Fuse block (J/B) connector E102
- 50A 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.
CHECK COOLING FAN CONTROL MODULE POWER SUPPLY CIRCUIT-III
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 WIRING DIAGRAM .
  
  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.
CHECK COOLING FAN RELAY
Refer to "COMPONENT INSPECTION ".

OK or NG

OK: GO TO 16.

NG: Replace cooling fan relay.
CHECK INTERMITTENT INCIDENT
Perform "TROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENT ".

OK or NG

OK: Replace IPDM E/R. Refer to "IPDM E/R (INTELLIGENT POWER DISTRIBUTION MODULE ENGINE ROOM) ".

NG: Repair or replace harness connectors.