2000 Tahoe, front and rear air, climate controled. Now the question. Can the climate control have anything to do with the way the AC works? I know that sounds like a stupid question but here is why I ask... I've had almost everything replaced. The only thing that wasn't replaced was the... ok here's where I get confused... the condensor... or evaporator coil???? It's the part that is under the dash inside... everything else was replaced. In my opinion it still isn't quit right.

Without using the "auto" mode I turn the fan on high and idling it blows almost 40 degrees. I turn on the rear air and the front temperature starts creeping up to about 55 degrees.

I'm wondering IF the climate control could be malfunctioning causing something to screw up when turning on the rear air. Everything in the rear AC has been replaced.

Any ideas????

 

Th evaporator coils are inside the cabin. 55 sounds about right. When you turn on the rear air it heats the freon up even more because now the rear fan is blowing warm air over the rear coil.