My fan on my car will not turn on when its supposed to! i have to turn the ac when i notice it is heating up, which is irrating anyway know where the relay is

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There is a fan relay in the fuse box, engine bay, I believe, but if your fan kicks on with the A/C it should be ok; check the coolant temp sensor in the water neck or outlet under the power steering pump, that is the bug that sends a signal to the PCM to kick on the cooling fan.