A c

low on refrigerant, compressor fuse blown, is the compressor spinning?

yes the conpressor is spining and i can hear and see the clutch engaged

So if the compressor is working, there may be a problem with the heat blend door in the vent, maybe it's stuck. When you change temp in the car, can you hear the door moving?

the air gets hot is there a way to see the door opening closing

Tommy Compton had is similar problem on 3-12-09 , although his problem was that the passenger side heat was hoter then the drivers side. Maybe look at his post or send him a PM to see if he has any suggestions.

http://www.cadillacforums.com/forum...003-through-2007/162830-blend-vent-motor.html

all vents are working one thing i notice the once i turn the ac on the compressor stays on it does not go on and off like it should

Maybe it doesn't cycle because the car doesn't get cool and the system thinks it needs more cold, so it keeps the compressor on. Just a guess. I'd go after the vent mix door, I think it's letting in too much warm air.

Or I could be all wrong, maybe you are low on frion and it trying to work to get more cold in the car. I know that if the frion gets low enough, it will not allow the compressor to run.

What year is your CTS? Personally, I've never considered AC repair to be a DIY job for most people. I also find they always seem to require service after about 5 years.

-GT

it an 03