Radiator fan stuck on full speed
 

Both fans of my radiator turn on full speed as soon as I turn on the car. It could be 40F outside or 100F, it'll just be at max at all times. Every now and then I can hear the fan speed fluctuating down to like 80% speed, but I can't figure out what's causing it.

My coolant temp gauge shows normal temps, below the middle. I tried switching out the fan relay (PWM RAD FAN RELAY) and that didn't work either.

What else could be causing this?

I tried cycling the AC to see if it'll stop it.. nothing.

First thing I'd do is check all the connectors in the circuit for looseness, corrosion, bent pins, etc. Connector and wiring harness locations (and much more) are in the FSM (link in sig).

I'll give it a good read right now. Thank you!

Did this just randomly occur? Did you get a tune recently?

My tune is setup up for 100% fan all the time.

No, it just came up out of nowhere. Car is 100% stock :confused:

Is it bad for the car to be at 100% fan? I mean, I'm sure the extra cooling will be nice in the summer..

I am having this same issue going on with my car. It did it this morning and it was 34 degrees.. Lol. Would love to know if this is bad or not for the car!

Fans will run if the A/C is turned on regardless of the outside temp...

Fan control module most likely shorted. Usually this would be caused by stuck temp switch or relay but I believe our cars get the fan on/off switch straight from Ecu to the fan control at the fan shroud.

Which temp switch are you talking about?
I am having the same problem and I know my ambient temps switch is bad

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Our cars fan isn't switch controlled. The control module gets signal directly from ECU to turn on/off the fan based off of coolant temperature sensor. So if your temp on dash is correct then the ECU gets proper coolant temp. Faulty ambient temperature sensor would cause issues with heat or ac not functioning correctly. Nothing to do with radiator fan.