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Can a mechanic wire the cooling fan of vehicle wrong? I had my vehicle serviced for an overheating problem and when I got it back it was blowing hot air when I turned on my a/c? My a/c was working when I took it in! ______________________________________________
It is possible that when the mechanic was servicing the engine cooling system, he accidentally disconnected a vacuum line to the AC air duct valve system.
You will probably get a better answer by identifying the vehicle and describing what the servicing mechanic did.
Rodan.