The first step is to check the cooling fan related fuse and relay. Check the fuse panel diagram in your owner’s manual to the appropriate fuse and relay. Look for any short circuits or broken connections.
2. Fan Switch or Coolant Temperature Sensor
The fan switch or the coolant temperature sensor is responsible for sending signals to the ECU on the engine temperature. When the temperature reaches the set limit, the switch will signal the ECU to turn on the radiator cooling fan.
Check both the fan switch and the coolant temperature sensor for any defects. If any problems occur, replace them with new ones.
3. Wiring Issue
If all the electric parts work well, there may be a wiring problem. Check for loose connections, or broken or grounded wires.
If the wiring is broken or grounded, replace the entire wire.
4. The Water Pump
If the water pump fails, it can cause cooling fan problems.
When the water pump is malfunctioning, it cannot adequately pump coolant through the engine, leading to overheating. As a result, the cooling fans may not turn on.
You should remove and inspect the water pump if you cannot see visible leaks outside the water pump. If you see leaks or any problem, please replace the water pump.
5. ECM Failure
If you have checked the above parts and everything seems to be OK, the last suspect will be the ECM( engine control module).
As a complex electronic component, it can develop different problems due to heat, vibration, and other factors.
Therefore, if you can’t find the problem with any other parts, you should test your ECM. You will likely have to take your car to a trusted mechanic to test the ECM.
