What causes cooling fan to stop working?

Six things may prevent an electric cooling fan from coming on: Defective temperature switch, coolant sensor or other sensor. Engine thermostat is stuck OPEN (engine never gets hot enough to turn on the fan) Faulty fan relay.

Are both cooling fans supposed to run?

Both radiator fans should always run when the AC compressor is engaged. Both radiator fans should always run when the coolant temperature sensor in the bottom tank of the radiator reaches about 212*F.

How much does it cost to fix a cooling fan?

The average cost for a replacement fan is between $634 and $789. Labor costs are between $102 and $130 while parts are between $532 and $659.

What does a bad cooling fan sound like?

A loud whirring Noise In some cases, when the radiator cooling fan motor fails, you’ll notice a loud clicking or whirring noise that changes as you rev your engine. Bad radiator fan noise might be so loud, but fixing it on time will save you from the expensive repair costs.

Should radiator fan turn on when AC is off?

Both radiator fans should always run when the AC compressor is engaged. To check the temperature at which the fan comes on, turn the A/C off and keep the engine running until it reaches normal operating temperature. Most fans should come on when the coolant reaches about 200 to 230 degrees.

How do I check the cooling fan in my car?

How to Check a Radiator Fan

Determine whether your radiator fan is manual or electric.
To check an electric radiator fan, start the car and let it get up to the temperature where the fan normally kicks on.
Use the volt meter to test if there is power to the wires.
Normal voltage for a radiator fan is around 12 volts.

Why is my Mercedes radiator fan running on high speed?

Please try again later. This is a very common problem with the Mercedes radiator cooling fan running constantly on high speed. The problem in most cases is a bad ecm so in order to fix it the ecm will have to be replaced and programmed to work with your vehicle. Check the mass airflow sensor first.

When does the radiator fan turn on in a car?

There is a sensor on the bottom passenger side of the radiator. It does the job of taking notes of coolant temperature. It sends signals to the radiator fan to turn on when the temperature crosses 172°F.

What should I do if my radiator fan is not working?

A blown fuse is no big deal, and changing one does not cost a lot of money. If your car’s radiator fan is non-functional, check your car’s user manual and locate the fuse for the radiator fan controller or the fan. The fan itself often uses a big fuse of around 50A, while there might also be a separate small fuse to the fan control module.

Why are the fan relays on my car not working?

Losing one relay (sub fan relay) can cause both fans to be off when the system is calling for slow speed operation. But if the car is overheating both fans should be running at high speed, in which case, if the sub fan relay has failed, the main fan will still function. On page 2, I posted a wiring diagram. second page).

What does it mean when your radiator fan is not working?

This is what we call a blown fuse. A blown fuse is no big deal, and changing one does not cost a lot of money. If your car’s radiator fan is non-functional, check your car’s user manual and locate the fuse for the radiator fan controller or the fan.

How does a radiator fan work in a car?

The fan should also turn on after switching on the air conditioner. Positioned between the radiator and engine, cooling fans blow cooling air through the car’s radiator to cool down the heated water and coolant mixture that flows through the radiator. The radiator fans blow cooling air through the car’s radiator. Source: Adobe Stock

Where is the relay on a radiator fan?

The fan relay is often located in the engine bay’s fuse box, but the best way is to check your repair manual to find where it is located. Testing a 4 pin relay is often very straightforward. Remove the relay and give 12 volts to pin 30 and 85. Ground pin 86 and check if there is voltage coming out from pin 87.