cooling fans - PartsMax

What to do When Your Car’s Cooling Fans Aren’t Working

A vehicle’s cooling fans serve a very important purpose; they cool the radiator and prevent overheating. If there are issues with the radiator fan, taking care of them right away will prevent serious damage. There are a few common cooling fan problems, and if your car has one or more of them, the fix is usually easy. Here, you’ll learn how to troubleshoot cooling fan problems, and you’ll also learn when it’s okay to drive without a working fan.

Check the FuseWhenever an electrical component stops working, fuses are the first (and easiest) thing to check. If you’re not sure where the fuses are located, refer to your owner’s manual to learn which fuse controls the system. Make sure it’s intact; if not, replace it right away, and the problem should disappear.

Look at the Fan Wires

If the engine is getting hot but the fan isn’t coming on, take a look at the fan wiring. Begin by unplugging the positive and negative feed wires, which should put out approximately 12 volts DC (direct current). With a voltmeter, verify that there’s currently available. If not, check the wires and the relay to determine whether it’s time to replace them. The fan relay is under the car’s hood. If there’s a voltage from the fan to the relay, the fan may be faulty and in need of replacement. Be sure to choose a fan with the proper CFM rating for the vehicle.

Check the Temperature Sensor

Temperature sensors read the system’s temperature to determine when it’s time to turn the fan on. If the sensor is non-functional, the fan won’t come on, and overheating may result. This sensor is usually found in the thermostat cover. Check it by disconnecting the wiring from the sensor and touching them together. If the fan starts, the sensor may need replacing.

Look at the Coolant Level

Next, check the engine’s coolant level by looking at the reservoir. It should be marked with minimum and maximum levels. Make sure the level is at or near the maximum mark to prevent engine overheating.

Check the Fan Clutch

The fan clutch keeps the fan on the engine and helps it to turn. If it fails, it must be replaced right away. The springs within the fan clutch may corrode or wear out with time. If all other parts seem to be working normally, the clutch is likely the cause of the fan’s failure.

Why You Can Run Without a Fan (and Why You Shouldn’t)

The fan draws air in and over the radiator, where it cools the coolant that flows through the engine. When the fan isn’t working, air will still flow in via the radiator shroud. However, flow rate and air temperature are now dependent on vehicle speed. In heavy traffic, airflow may be restricted, but on an empty road, it may be sufficient so that the car won’t run hot. The fan is a crucial part of a vehicle’s cooling system, and if it stops turning, overheating, head gasket failure and expensive repair bills are the most likely result.

Keeping the Fan Running

To minimize the chances of cooling fan failure, occasionally adjust and inspect the fan belt. If it’s old, cracked, and dry, replace it right away. On cars with electric fans, be sure the wiring is in good condition. Be sure to keep an extra fuse and a relay (if needed) in your car in case of a failure while driving. The cooling fans are one of your vehicle’s most important parts, and without them, your engine will overheat very quickly. By following these troubleshooting tips, you’ll keep your car running cool for years to come.