Cadillac Repair: A/c issue, computer modules, pressure sensor

Question
My in dash readout will say A/C compressor off,very low refrigerant. My mechanic says if he slaps computer module it works ok temporarily, What should I do? A new module is anywhere from 550.00 to 850.00. any suggestions. Engine is a Northstar, 97 deville, vin1G6KD54Y8VU250857. Thank You

Answer
Computer modules only cost about $150.00. Your problem is either:

low refrigerant (freon) in the system.

A faulty low pressure sensor.

a faulty low pressure switch.

If you are mechanicaly inclined or know of someone who is,  You will need simple electrical schematics, Test procedures and picture locations of the components within the system that is causing you problems of which can't be done on this website which only allows one picture. I do not have a website so you will have to e-mail: onlineautohelp@msn.com in order to obtain the information.