Common questions

What does a cooling fan relay do on a car?

What does a cooling fan relay do on a car?

A cooling fan relay is used on vehicles that have an electrical fan to cool the engine. The function of the cooling fan relay is to convert a low voltage signal from either the electronic control module (ECM) or a thermostatically controlled sensor.

How do you check the cooling fan relay?

Verify the operation by energizing the cooling fan relay. This is done by either warming the engine up to operating temperature or by turning on the air conditioning system. Note: Most, but not all, manufacturers have the cooling fan system designed to come on when the air conditioner is turned on.

What happens when the fan relay does not work?

By using a lower voltage signal to control the relay, there is less stress on the rest of the wiring and charging system. When the fan relay does not work, then the proper signal will not be received and the fan cannot cool the system down.

Why are the cooling fans not working on my car?

1. Engine running hot 2. Cooling fans do not function 3. Cooling fans stay on at all times Average rating from 129,472 customers who received a Vehicle Engine Cooling Inspection. Most modern vehicles use electric cooling fans to help pull air through the radiator so that it can keep the engine cool.

How does the cooling fan relay work on a car?

The cooling fan relay is the relay that controls the engine’s cooling fans. When the correct parameters are met, a temperature switch or the computer will activate the relay, which will allow power to the fans. The relay will usually be activated once it is detected that the vehicle’s temperature…

What are the symptoms of a bad cooling fan relay?

1. Engine running hot One of the first symptoms commonly associated with a bad or failing cooling fan relay is an engine that runs hot or overheats. If you notice that your engine is running at higher temperatures than normal, that may be a sign that the relay is not functioning properly.

When do you turn on the fan relay?

When the correct parameters are met, a temperature switch or the computer will activate the relay, which will allow power to the fans. The relay will usually be activated once it is detected that the vehicle’s temperature approaches excessively high temperatures.

How does the p0480 cooling fan relay work?

The PCM (powertrain control module) senses the increase in engine temperature through the CTS (coolant temperature sensor) located near the thermostat. When the temperature reaches about 223-degrees F (value depends on make/model/engine), the PCM will command the cooling fan relay to turn on the fan.

Author Image
Ruth Doyle