Q: Heater core is clogged. cooling fans are shorting out, yesterday had to pull over because temperature gauge went to H. Later that

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Heater core is clogged, I think cooling fans are shorting out. I had to pull over yesterday because I noticed the temperature gauge was all the way to H. I let it cool off then parked my car, later that day I drove it back home and it was fine, it did not overheat, suggestions? What could of caused the cooling fans to not start? Later when I drove it back home for about 20 miles, it did not overheat at all. Suggestions?

My car has 106000 miles.
My car has an automatic transmission.

Hello, thank you for writing in. The vehicle may be suffering from several types of issues, and may have more than one issue at once. With that being said, if you know the cooling fans were not turning on when they should, you should turn your attention there first. When the system detects that your engine temperature has warranted the fans to turn on, the fan relay energizes and sends power to the fan motors. Due to the problem being intermittent, you may want to ignore the relay for now, as they typically work or don’t. You may want to start by flushing the cooling system to make sure that the radiator and heater core are allowing coolant to flow freely. You can also test the fan motors to see if they are experiencing any electrical issues. The last component that you will want to check before turning your attention elsewhere would be the engine temperature sensor, which dictates to the computer when the fans need to turn on. Only further testing will tell.

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