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Q: Car overheats causing me to fail emissions

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My car gets really hot into the 195 on the temperature gauge. The check engine light came on I got a free diagnostic from auto zone they told me it was the fan Colling relay. I went to the emissions and was told the same thing. They gave me this code P0480 which I purchased and replaced with a new relay. Nothing changed. When I call a mechanic they said it would be over 300 dollars to fix so I imagine that the its more to fixing the problem then just replacing the relay which is right on top easily assessable and just snapped right into place. I want to know if there are more steps replacing the cooling fan motor relay that would make the check engine light go off and keep the engine cool. Want to stay on the less expensive side. I would take to a shop later but right now I need to pass my emissions so I can get new tabs and the p0480 code is what pops up. Also the guy I purchased from ran the fan switch into the car so it could be turned on manually my guess is he had the same problem

My car has 182000 miles.
My car has an automatic transmission.

A: The cooling fan is controlled by the relay....

The cooling fan is controlled by the relay. The relay is turned on and off by the engine control module. The engine control module gets the temperature control from the coolant temperature sensor. The code P0480 sets of when the ECM detects a problem with the cooling fan relay circuit. The circuit is bypassed if you say it has a switch inside. You will need to put the circuit back to original and then see if the ECM will turn on and off the relay. The problem may be in the ECM circuit and this is why it was bypassed and put on a switch.

You may need a new ECM if it does not turn the fan on and off electronically. If you decide to get this problem fixed, consider enlisting a qualified mechanic who can accurately diagnose your overheating issue and make the necessary repairs to your vehicle.

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