Cooling Fan Control Inspection

Cooling fan operation

Cooling fan
1. Verify the engine is cold.
2. Turn the ignition switch to ON.
3. Verify the cooling fan is not operating.
4. If the cooling fan is operating:
1. Connect the SSTs (NGS tester) to DLC-2.
2. Select the SIMULATION TEST. Then, select FAN2 in IG ON TEST.
3. Send OFF signal and verify that the cooling fan is OFF.
4. If the cooling fan is ON, inspect for the following:
- Cooling fan relay stuck in closed position.
- Short to GND circuit between cooling fan relay and PCM terminal 2B.
- Short to power in circuit between cooling fan relay.
- DTCs for ECT sensor.
- P0116, P0117, P0118, P0125, P0126, P0128

5. If the cooling fan is OFF, inspect for the following.
- Short to GND circuit between A/C switch and PCM terminal 4F.
- DTC for ECT sensor.
- P0116, P0117, P0118, P0125, P0126, P0128

5. Start the engine.
6. Verify that the cooling fan is operating when engine is hot.
7. If the cooling fan does not operate, perform as follows.
1. Connect the SSTs (NGS tester) to the DLC-2.
2. Select SIMULATION TEST mode.
3. Select IG ON TEST mode.
4. Select FAN2.
5. Press START.
6. If the cooling fan operates, inspect the ECT sensor DTCs.
- P0116, P0117, P0118, P0125, P0126, P0128

7. If the cooling fan does not operate, perform as follows.
- Select FAN3. Operate cooling fan by selecting START, and verify that operation sound is heard from the cooling fan relay.
- If the operation sound is heard, inspect the wiring harnesses, connectors, and the cooling fan motor.
- If operation sound is heard, inspect cooling fan relay and open circuit in wiring harnesses and connectors.

8. Turn the A/C switch and fan switch on.
9. Verify the cooling fan is operating.
10. If fan does not operate, inspect A/C system.

Condenser fan relay
1. Verify that A/C switch and fan switch are off.
2. Start the engine and let it idle.
3. Verify that the condenser fan is not operating.
- If condenser fan is operating, inspect for the following.
- Condenser fan relay is stuck in closed position
- Short to power in circuit between condenser fan relay and condenser fan
- Short to GND in circuit between A/C pressure switch and PCM terminal 4F
- Short to GND circuit between condenser fan relay and PCM terminal 2C (short circuit)

4. Turn the A/C switch and fan switch on.
5. Verify that the condenser fan is operating and operating sound of A/C compressor magnetic clutch is heard.
6. Turn the A/C switch and fan switch off.
- If the condenser fan does not operate but operating sound of A/C compressor magnetic clutch is heard, inspect for the following.
- Open circuit between ignition switch and condenser fan relay
- Open circuit between battery and condenser fan relay
- Open circuit between condenser fan relay and PCM terminal 2C
- Open circuit between condenser fan relay and condenser fan motor or fan motor GND
- Condenser fan relay is stuck open
- Condenser fan motor

- If both condenser fan and A/C compressor do not operate, inspect the following.
- TP V PID
- A/C system