Q: Cooling fans

asked by on October 14, 2016

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.

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?
The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details

Get an instant quote for your car

Our certified mechanics come to you ・Backed by 12-month, 12,000-mile guarantee・Fair and transparent pricing

Get a quote

What others are asking

Steering to the right or left makes a noise.

I believer the cause of your noise is your power steering pump or belt. If your pump is making a loud whining noise then you may have a power steering leak and the pump is starving for fluid. Check the...

Engine lost power, but then started after sitting for a while.

Hello, There are many things that could cause your vehicle to lose power as you describe, however what you are describing sounds like potentially a failing ignition coil. A failing ignition coil will often times produce a symptom as you...

No heat?

You most likely have low coolant in the system and need to purge the air out of the cooling system. Have the cooling system checked and purged of air then test the heater again.

Related articles

How to Tell If Your Car Switches Are Dying
Since Since every part of your car is controlled or operated by a switch in some fashion, it is to be expected that the switch will eventually fail. Some of the most commonly used switches in your car are: ...
Symptoms of a Bad or Failing Cooling Fan Resistor
Common signs include the engine overheating, cooling fan only working at certain speeds, and the fan never turning off.
What Are Rocker Switches and How Are They Used in Cars?
Every Every function inside your vehicle is controlled by a switch in some way. Some switches require a high current capacity, while others are low voltage. Low voltage switches usually control the electrical position of a relay, which directs a...