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Q: My radiator fan only turns on when my AC turns on.

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My car has been over heating when my AC is off.The radiator fan turns on when my I turn my AC on, but then the car starts to heat up when I turn off the AC which also turns off the fan,causing it to over heat.

My car has 180502 miles.
My car has a manual transmission.

A: Hello there, a couple of different items ca...

Hello there, a couple of different items can cause the fan to not work like this. The most likely culprits are a thermostatic switch, fan resistor, temperature switch, low-speed or high-speed relay, or a wiring issue. If the vehicle overheats, care should be taken when driving to prevent further damage by overheating. When the vehicle has the AC on, the engine needs extra help cooling so the ECU commands the fan to be on any time the AC is on. A qualified technician, such as one from YourMechanic, will be able to diagnose your overheating problem and perform any repairs required.

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