Cooling fan does not turn on

ALEXEI NIKOLAYEVICH

MEMBER
2007 KIA AMANTI
99,000 MILES

And casually I have another problem with my cooling system.
My radiator fan doesn't turn on, and one round trip 20 miles, the car got overheated.
After that, it turned out the fan doesn't turn "on" when overheating.
I connected the fans directly to the battery, and both fans worked.
After that I checked the system turning on A/C, same results, the fan didn't start.
Now I want to check the fan circuit, but I don't know the location of the relays responsible for the fan operation?
If possible could you give me an idea where can I start to find the reasons for not working fans? Thank you.

3 Replies

SQM

MECHANIC
6,383 POSTS

Hello,

Anytime you have an inoperative fan the first item to check the fan relay. Since you know the fans are good then the fans are not working due to not getting power to them. A bad relay will keep the fans from working.
The relay is located under the hood (see picture below).
Check for any corrosion or burnt pin(s). You can also test the relay.

https://www.2carpros.com/articles/how-to-check-an-electrical-relay-and-wiring-control-circuit

If the relay is good then the next item to check is the coolant temperature sensor. A faulty sensor may not send signal to the ECM to start the fan when the engine is at the operating temperature.

https://www.2carpros.com/articles/how-a-coolant-temperature-sensor-works
https://www.2carpros.com/articles/symptoms-of-a-bad-coolant-temperature-sensor

Please let me know what you find or if you have any questions.
Thank you.

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