A really "quick and dirty" check is to unplug the low pressure switch wiring connector from the receiver-dryer, then take a paper clip opened out to a U-shape and insert it into the wire receptacles (for a few seconds) inside the connector. (Not the switch). If the problem is low refrigerant pressure, this will temporarily bypass that safety circuit, and should allow the compressor clutch to power up and operate. Do not do this as a bypass to continue operating, it's simply a troubleshoot procedure. If it does allow the syestem to work, your system has definitely defaulted to a safety-off condition because there's not enough refrigerant (and possibly oil) to keep all the moving parts lubed. Find/repair your leak, check the oil and recharge the system. Enjoy the "cubes"
