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Q: fans, air conditoning, electrical wiring

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My air conditioner is not turning on the fans automatically. The car only cools when it's moving. They only turn on automatically when the car has reached operating temperature. The freon is full and the system has pressure. The AC compressor turns on, too. My brother recommended I have the 2 fans hooked up directly. That way the fans are always running when the car is turned on. But I would have to hire an electrician to do this. Do you know what the problem is?

The condenser fan is a separate circuit from the radiator fan. It sounds like the radiator fan is being controlled properly by the powertrain control module as the fan is activated by the engine temperature.

The condenser fan is a 2 speed fan that is controlled by 2 relays in the engine compartment fusebox. It is possible that the low speed relay has failed and is preventing the fan from working.

Replacing the two relays may be an inexpensive fix to this issue. We never recommend altering the vehicle wiring for fan operation at all times as this will make it harder for the vehicle to reach operating temperature, which can cause a whole mess of other problems including lower gas mileage and increased emissions.

You may want to enlist the help of a mechanic, such as one from YourMechanic, who will have the tools and expertise to diagnose the AC system and make the appropriate repairs.

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