What Causes the Cooling Fan to Stop Working?
2 Answers
Cooling fan not working is caused by water temperature not meeting requirements, relay failure, or thermostat switch issues. Here are the details: 1. Water Temperature: Most modern car radiator fans operate with electronic temperature control, so the fan will only start running normally when the engine coolant reaches the required temperature. If the temperature is too low, the radiator fan will not operate. 2. Relay Failure: If the water temperature meets the requirement but the car radiator fan still doesn't work, it may be due to a faulty fan relay. If the relay malfunctions, the car's radiator fan won't operate. 3. Thermostat Switch Problem: If neither of the above issues is present, there might be a fault with the thermostat switch, which can also affect the operation of the car radiator fan. Therefore, it's important to check this component as well.
Last time my car's fan suddenly stopped working, it took me a while to figure out the issue. The most common cause is a faulty temperature sensor—if it can't accurately measure the coolant temperature, the computer won't send the start command. Another possibility is a blown fuse, especially during peak electricity usage in summer when they're prone to melting. The relay is also crucial, as oxidized contacts can render it useless. Loose wiring connections are worth checking too, particularly in the high-temperature engine bay where poor contact is common. Motor failures are less frequent, but worn carbon brushes or seized bearings do happen. Actually, replacing the fan isn't too expensive, but don't rush into it—using a diagnostic tool to read trouble codes is the most reliable approach, since modern cars are highly electronic.
