Q: Cooling fans running all of the time

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My cooling fans start immediately when I start the car, even on cold days, and stay on until I turn the engine off.

There are a couple possibilities. The engine’s computer controls the fans. If it does not have the proper input from the coolant temp sensor or other vital sensors, it can turn the fans on all the time by default. The Check Engine Light is most likely be on. The other most likely problem would be a faulty fan relay. It could be stuck on. The relay only has source power when the key is turned on. Either way, scanning the car’s computer would narrow down where to look for the culprit.

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