AC problem

Took my '97 Aurora to Tune-up plus. Because I didn't have any AC. After checking the system, and installing some freon. He wanted $750.00 to install a AC/Heater control panel. I found one on-line for $100.00, plus $15.00 shipping. And installed it myself. Still no AC. I took it back, and the AC started working. He said it was a loose connection. The next day, no AC. So I am trying to figure out. Where that loose connection, could be. The only connection, i can think of, is the one on the compressor. Guesses anyone, because i don't want to take it back to that mechanic. Even though I paid him $179.00, for the system check and freon.

did you check the fuse?

you get an A/c request signal that comes out of the climate control, goes through the steering rack, The High pressure side over pressure switch, the low pressure switch, Some have a switch on the back of the pump itself.

Then it goes to the A/C clutch

Took my '97 Aurora to Tune-up plus. Because I didn't have any AC. After checking the system, and installing some freon. He wanted $750.00 to install a AC/Heater control panel. I found one on-line for $100.00, plus $15.00 shipping. And installed it myself. Still no AC. I took it back, and the AC started working. He said it was a loose connection. The next day, no AC. So I am trying to figure out. Where that loose connection, could be. The only connection, i can think of, is the one on the compressor. Guesses anyone, because i don't want to take it back to that mechanic. Even though I paid him $179.00, for the system check and freon.

The system has 2 switches. A High pressure cut out switch. Located on the rear, lower, left side of the compressor. And a Low pressure cut out switch. Which I am trying to locate. According to my manual, its on a tube that goes through the fire wall. I think its on the inside of the fire wall, behind the instrument panel.