Why do I need to check my cooling fan relay?

The cooling fan relay essentially functions as the switch for the engine’s cooling fans; and is therefore an important electrical component of the vehicle’s cooling system. Finally, if you suspect that your cooling fan relay, may possibly be having issues, have it checked.

Why does my blower fan only work on one speed?

by Lee Sallings. The most common symptom of a faulty blower motor resistor is a blower fan that only works on one speed, usually high. This can be annoying, but troubleshooting is easy. If you start at the blower motor, and check resistance in the circuit, you will find the problem in no time.

What happens if one fan fails to come on?

If one or both fans fail to come on; the lack of additional cooling provided by the fan may cause poor A/C cooling performance. Also, it may cause the A/C compressor to overheat and fail. The engine may also run hot and overheat, too.

How can I tell if my cooling fan is working?

The quickest way to tell whether or not the electric fan (s) are working is to start the engine; let it reach normal operating temperature and then turn the A/C on. The cooling fan in the engine compartment should turn on to pull air through the radiator and A/C condenser. A main cooling fan for the radiator.

How to troubleshoot an electric cooling fan problem?

1.Has the Cooling Fan Actually Failed? 1 If the fan comes on when the AC is running at MAX, but doesn’t run when the engine is hot, check the temperature sensor… 2 If the fan fails to come on, first check for a fan blown fuse or triggered breaker. On older vehicle models, you may… More

Why are my cooling fans running at all times?

3. Cooling fans stay on at all times. If the cooling fans are staying on at all times, this is another (less common) symptom of a possible problem with the cooling fan relay. If the relay shorts internally, it may cause power to be permanently switched on, which will cause the fans to run at all times.

How can I test if my engine cooling fan is working?

That’s why you will need to test it. Unplug the fan connector closest to the fan. Make up some jumper cables. Then connect them directly, from the battery to the fan motor, to see if it spins. Consequently, if it does not spin it is blown.

Do you need to test the thermostat switch?

The first components that should be tested are the cooling fan, the cooling fan relay and the thermostat switch, which turns the fan on and off depending on the temperature of the engine. The thermostat switch can be tested easily after it has been removed from the vehicle.

When do I need to test my car fan?

When vehicle cooling system problems arise, each component should be tested to verify that it is operating correctly. The first components that should be tested are the cooling fan, the cooling fan relay and the thermostat switch, which turns the fan on and off depending on the temperature of the engine.

Can a bad fan relay cause an engine to overheat?

However, a bad cooling fan relay isn’t the only culprit for excessively high engine temperatures. Many other issues can cause the engine to run hot or overheat. Rather than uncommonly high engine temps, the driver may notice that the cooling fans have stopped running.

What to do if your ECM power relay is failing?

For this reason, if you suspect that your ECM power relay may be having an issue, have the vehicle inspected by a professional technician, such as one from YourMechanic, to determine if the relay should be replaced. The most popular service booked by readers of this article is Vehicle Engine Electrical Inspection.

How can I check if my Clutch relay is still running?

Check all three wires with the test light; with the engine running, the wires should all be inactive. With the engine running, turn the A/C control or switch to “on” at the dashboard. Check the three wires again.

What should I do if my relay has failed?

Turn the ignition to the “ON” position and jump terminals 87 and 30 the relay is now jumped and the accessory should activate, if so the relay has failed. If no power is observed at either 87 or 30, the fusible link or maxi fuse has shorted.

How do you test a car relay with no power?

If there is no power, the electrical system must be tested starting with the fuse then the relay. If power is present use the test light connected to battery power to check the ground circuit. if these tests check out, the accessory is bad and needs to be replaced.

How is the electrical system of a relay tested?

Why do I need to check my cooling fan relay?