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Q: Issue with my A/C, what is the most likely problem?

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My trucks ac has worked flawlessly all summer this mornitwas the first real cold snap. I adjusted the temperature to warm this morning on the way to work this afternoon when I got back in the truck the air will do nothing but blow warm air. I have checked all fuses I have checked the fan and compressor they Both activate when the ac is turned on. I have no reason to believe I'm low on coolant it has always blown very cold. I suspect the temp control module has malfunctioned because there is no noticeable change in temperature when I turn it all the way to hot or cold. How do I test my theory

My car has 76000 miles.

A: Hi there. In many cases when the AC suddenl...

Hi there. In many cases when the AC suddenly stops blowing cool air, it’s due to a faulty temperature control module (as you indicated) or you’ve developed a vacuum leak somewhere in the system.

You can test this by completed an AC performance test using a manifold gauge set. When you hook up the gauges you’re testing the pressure on the low and high side of the system to determine if a leak exists. If the levels are equal, it’s likely either a refrigerant level or the temp control.

If you’re not able to complete the pressure test, contact one of our professional mechanics and they’ll be happy to diagnose the issue with your A/C for an accurate repair.

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