Diagnosis Procedure
- CHECK COOLING FAN SPEED SENSOR POWER SUPPLY CIRCUIT-I
- Turn ignition switch OFF.
- Disconnect the fan clutch assembly harness connector.
- Turn ignition switch ON.
- Check the voltage between the fan clutch assembly harness connector terminals.
Fan clutch assembly
Voltage
(Approx.)
Connector
+
-
terminal
F97
2
4
5 V
Is inspection result normal?
YES
GO TO 6 .
NO
GO TO 2 .
- CHECK COOLING FAN SPEED SENSOR POWER SUPPLY CIRCUIT-II
- Check the voltage between the fan clutch assembly harness connector and the ground.
+
-
Voltage
(Approx.)
Fan clutch assembly
Connector
terminal
F97
2
Ground
5 V
Is inspection result normal?
YES
GO TO 4 .
NO
GO TO 3 .
- Check the voltage between the fan clutch assembly harness connector and the ground.
- CHECK SENSOR POWER SUPPLY 2 CIRCUIT
Perform Diagnosis Procedure .
Is inspection result normal?
YES
Perform the trouble diagnosis for power supply circuit. Refer to Diagnosis Procedure .
NO
Repair or replace error-detected parts.
- CHECK COOLING FAN SPEED SENSOR GROUND CIRCUIT
- Turn ignition switch OFF.
- Disconnect ECM harness connector.
- Check the continuity between the fan clutch assembly harness connector and ECM harness connector.
+
-
Continuity
Fan clutch assembly
ECM
Connector
Terminal
Connector
Terminal
F97
4
F78
43
Existed
Is inspection result normal?
YES
GO TO 5 .
NO
Repair or replace error-detected parts.
- CHECK ECM GROUND CIRCUIT
- Turn ignition switch OFF.
- Disconnect ECM harness connector.
- Check the continuity between ECM harness connector and the ground.
+
-
Continuity
ECM
Connector
Terminal
E16
147
Ground
Existed
149
152
Is inspection result normal?
YES
Check intermittent incident. Refer to Intermittent Incident .
NO
Repair or replace error-detected parts.
- CHECK COOLING FAN SPEED SENSOR SIGNAL CIRCUIT
- Turn ignition switch OFF.
- Disconnect ECM harness connector.
- Check the continuity between fan clutch assembly harness connector and ECM harness connector.
+
-
Continuity
Fan clutch assembly
ECM
Connector
Terminal
Connector
Terminal
F97
5
F78
31
Existed
- Also check harness for short to ground and to power.
Is inspection result normal?
YES
GO TO 7 .
NO
Repair or replace error-detected parts.
- CHECK COOLING FAN SPEED SENSOR
- Reconnect all harness connectors disconnected.
- Perform cooling fan speed sensor component inspection. Refer to Component Inspection (Cooling Fan Speed Sensor) .
Is inspection result normal?
YES
GO TO 8 .
NO
Replace the fan clutch assembly.
- CHECK COOLING FAN ROTATIONAL CONDITION
Rotate the cooling fan by hand.
Dose the cooling fan rotates smoothly?
YES
GO TO 9 .
NO
Check that the cooling fan is not interfered with other parts.
- CHECK FAN CLUTCH ASSEMBLY CLUTCH ASSEMBLY SYSTEM
Refer to Diagnosis Procedure .
Is inspection result normal?
YES
Check intermittent incident. Refer to Intermittent Incident .
NO
Repair or replace error-detected parts.