[Deepstar]

Just brought 03 trailblazer, everything seem good until 5 days ago the weather here (SC) went from 20 to 80 in the same week. So I turned on the a/c on to find out its blowing hot air. Freon level is good, the a/c light comes on, and the blower direction works. However the climate control, it doesn't matter if its set on coldest or hottest just hot air come out. This happens on both side of car. Any information will be helpful.

 

[freddyboy61]

Some questions;

1) Do you have the Digital HVAC system?
2) Does the exterior temperature display properly on the Digital HVAC unit (if you have the Digital HVAC)
3) When you turn on the AC, do you hear the compressor come on?
4) Is the temperature at the vents really hot or just warm?

 

[Deepstar]

No mind is manual and yes I can hear the compressor come on, plus condensation builds up. Yes its hot even when the air is cool outside.

 

[freddyboy61]

The only reason I can come up with for hot air to be coming out of both driver and passenger vents is that both temperature actuators or doors are stuck in heat mode.
Try pulling the HVAC fuses #36 & #39 in the rear fuse panel, with ignition off. After a minute or so, reinstall fuses and turn the ignition to the on position (but do not start the engine). Do not touch any of the HVAC controls for about 90 seconds, it will be calibrating during that time. Then try running the AC and see if it works. If that does not fix the problem, you may need to have a tech look at it.