I need some help. A few days ago on my way home from work (Phoenix 100+ deg) my air was working fine about 20-25 minutes then started to blow warm air. I took it to our local fix it shop for our company trucks. They checked the refrigerant, to much they said, they charged it to the proper pressure and said it was working great. I said how long has it been running--long story short they test drove it - same problem 20-25 minutes, searched for a short from the compressor but couldn't find one. any one able to help???

Thanks,

sailfast

 

Have them check the pressures when the system isnt working. I suspect you have a moisture problem causing a blockage in an ac line once the system gets cold.

 

You know, you do have climate control diagnostics on that car.

Follow the instructions on this link to access the diagnostics:
http://www.audiworld.com/tech/int5.shtml