1. Faulty Fan Motor: The cooling fan motor itself may be faulty and unable to run. Check the fan motor for any visible signs of damage or corrosion, and try rotating the fan blades by hand to see if they move freely.
2. Faulty Wiring: There may be an issue with the wiring that connects the cooling fan to the relay and the power source. Check the wiring for any breaks, shorts, or loose connections.
3. Faulty Temperature Sensor: The temperature sensor may be faulty and not sending the correct signal to the relay to turn on the cooling fan. Check the temperature sensor for any signs of damage or corrosion, and test its resistance with a multimeter.
4. Defective Control Module: The engine control module (ECM) may be defective and not sending the correct signal to the relay to turn on the cooling fan.
To diagnose the exact cause of the problem, you can use a multimeter to test the voltage and continuity of the wiring and components involved in the cooling fan circuit, such as the relay, fan motor, temperature sensor, and ECM.
If you lack the expertise or tools to perform these tests, it is recommended to consult with a qualified mechanic or auto electrician to further diagnose and repair the problem.
