Q: Aircond fan turns on when radiator fan is on

asked by on November 23, 2017

My aircond sometimes blows warm air but it turns cold as soon as the aircond fan turns on (it turns on at the same time when the radiator fan turns on), But shouldnt the aircond fan be on when the ac is on and turns off when ac is off? Or is it about time for the aircond fan motor to be replaced? This only happens intimmitently though.

The a/c fan and engine cooling fan is controlled by the computer on most cars and should come on as needed to keep the engine from overheating and when the a/c is on. Since you did not supply the vehicle you have I cannot be more specific on the way your fans work. If you have a system that only turns on a/c fan when a/c is on then you may have an issue with the a/c control system if it does blow cold when fan is on and will need further diagnosis by a mechanic like one from YourMechanic.

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