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Q: A/C warm air and compressor comes on

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The compressor comes on when I turn on the air conditioning and the internal blower fan goes on high. But the condenser will not come on. The air from the A/C is never very cold. I have a friend who has a repair shop and we evacuated the system, plus used his machine to re-pressurize and refill it. That was all he could do at that time. In my thinking, it might be a relay problem. While under the hood, I looked at the relays near the fuse panel, however they are not labeled. Do you think it’s a relay problem and if so, could you tell me which one it is or where I can get a diagram? Thank you.

A: Hooking up a set of gauges will let you kno...

Hooking up a set of gauges will let you know if the expansion valve is working properly. There is an auxiliary fan control module that controls the condenser fan. It is fed power by a 20A fuse. The fuse and control unit need to be looked at to see if the condenser fan is being activated. If not, then the control unit and fuse need to be looked at. If there is an activation signal from the control unit and no fan operation, then the fan needs to be replaced. You may want to enlist the help of a mechanic, such as one from YourMechanic, who is certified to diagnose and repair your AC system issues.

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