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Q: Temperature rises when air or heat turned off

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When I have the air conditioner or heater on, the temperature stays normal. But when I turn the air or heat off, the temperature rises.

Hello. If the engine starts to overheat with the heater off or without the AC on, then it is usually caused by an issue with air flow through the radiator. You may have a failing fan relay or a circuit issue within the wiring. A voltage meter would need to be used to determine where the voltage is being lost. I would enlist the help of a certified mechanic, like one from YourMechanic, to inspect for any electrical problems and replace any bad fuses or relays.

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