Cadillac Repair: airconditioner, pressure gage, orifice tube

Question
I have a 1999 cad deville d'elegance with northstar eng. purchased in 4/2007. the ac was not blowing cold. I took it to ac service to have recharged. They said it was fully charged but the compressor keeps turning off. Any suggestions? thanks

Answer
The first things that they should have done are:

1. Put a set of AC gages on the system to see what the pressures are.

2. Remove all the freon from the system and replace the orifice tube.

3. Using a vacuum pump, Evacuate all the air out of the AC system and wait 15 minutes to be sure that the low pressure gage held 29"'s of vacuum.

4. If it held vacuum OK, Recharge the system and re-read the AC gages to see what the pressures are.

It could be a faulty:

LOW pressure switch.
High pressure switch.
AC compressor relay.

I can e-mail you a picture location of the LOW pressure switch and the AC compressor relay if you want to replace them and see what happens.

e-mail me at: onlineautohelp@msn.com