Skip the auto shop - Our mechanics make house calls

Q: Cooling fans

asked by on

My car has 2 fan spends hi and low... Only the low speed comes on and that's only if I turn the a/c on... I've changed relays fuses temp switch and thermostat... I bleed system burped it and flushed.... But the only way I can get the high fan to kick on is if I unplug the temp sensor which I replaced twice just in case the first one was faulty ... What could be the problem?????

My car has 145000 miles.
My car has an automatic transmission.

A: This can be caused by a number of things su...

This can be caused by a number of things such as low coolant levels, a faulty thermostat, or a failing coolant fan switch. As you may know the coolant fan switch helps to maintain the proper coolant temperature by turning on and off at specific temperature thresholds. When this switch is not working properly, this can cause the fans to come on intermittently, all the time or sometimes not at all. When this happens you will notice a temperature spike and drop occasionally as the fan comes on and off. I would suggest having an expert from YourMechanic come to your home to diagnose your cooling system.

Was this answer helpful?

Need advice from certified mechanic? Get help now!

Over 1000 mechanics are ready to answer your question.
The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details

Ask a Mechanic
(100% Free)

Have a car question? Get free advice from our top-rated mechanics.

Ask A Mechanic
Over 10,000 questions answered!

Get an instant quote for your car

Our certified mechanics come to you ・Backed by 12-month, 12,000-mile guarantee・Save up to 30%

Get a quote

What others are asking

Q: The front end and steering wheel shakes when I accelerate.

You may have a traction control system that is activating when you are accelerating. This can be due to one of two things: the speed sensors in the front detect that a wheel is going faster than it...

Q: My door does not lock or unlock. Would I need to replace a fuse or buy a new key?

I believe the door lock actuator has failed, not a fuse or key. BMW door lock actuators (part electric, part mechanical) have what is essentially a two-stage lock, and can fail and become "double-locked". Sometimes, exercising the "unlock/lock/unlock" cycle multiple...

Q: Door won't unlock with key

It sounds like you all keys for the vehicle had been lost and only the ignition key cylinder was replaced. If your keys do not work for the doors then you will need to have the [door lock cylinder replaced](https://www.yourmechanic.com/services/ignition-lock-cylinder-replacement...

Related articles

How Long Does a Distributor O Ring Last?
The distributor is part of the ignition system in your vehicle and its purpose is to route high voltage from the ignition coil to the spark plug. The spark plug then...
How Long Does a Heater Control Valve Last?
Keeping the right amount of coolant in a car is essential in keeping the engine at the right temperature. Failing to have the right amount of coolant or even bad elements...
How to Avoid Back Pain in a Car
If you have back problems, sitting in a car for an extended period of time can be excruciating. Even without back problems, you could experience discomfort and soreness from...