I just bought a 2004 gmc envoy. I seem to have a problem with the heat. After a while of the heat running one side at a time driveror passenger side will just start blowing cold or ambient air , then
Will go back to heat then repeats the same
process over and over.do u have any idea
what the issue might be.
You could try a reset by simultaneously pressing mode , front defrost, rear defrost. If that doesn't correct the problem you could have bad actuator sensors, as this system is quite involved in testing procedures I would recommend that you take it to a shop you trust fora system check out. Did you get any kind of warranty when you purchased it?
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