97 Ford Escort AC Inop?

I have a 97 escort wagon. The ac sometimes works and sometimes doesnt. I checked the pressure at the low side port and it was over 100 with the gauge that came with the R134a kit I got from AAP. I have read that if its over 100 that you cant add anymore refrigerant. What else should I be looking for ? When I turn the ac unit on in the car, the radiator fan automatically turns on but I dont hear the ac compressor engaging.
97 Ford Escort AC Inop?
Find clutch connector near compressor,and disconnect. Run a jumper wire from clutch to battery positive terminal,start engine. If compressor will not run,clutch on compressor is bad. If it runs,stop engine and re-connect factory wires. Find low pressure switch near low side port,resembles an oil pressure switch.


Disconnect wires to low pressure switch and jumper across wiring terminals for switch. This should make compressor run if AC is on inside car and engine is running. check pressures with compressor running. Suspect low refrigerant or bad electrical connection,or bad low pressure switch.
97 Ford Escort AC Inop?
find the low pressure switch on the receiver drier and disconnect. ck for power at the switch with the a/c on and the engine running. if there is power there jump across the connector and check for power at the compressor. if there is no power you have an open circuit in the poss wire to the compressor. if there is power and the compressor still is not on, ck and make sure the ground is good buy ohms testing it with a dovm. if it is good then the compressor clutch has failed. you can replace the compressor clutch without replacing the compressor. if everything works fine when jumpering across the low pressure switch get a low pressure swtich and replace it. there is one other thing that could cause this problem. the a/c or wide open throttle cutout relay may be failing to open back up after a hard acceleration.