47-55.1 Any AC experts?

[chevyguyase]

If your expansion valve is stuck closed your low pressure side will be low because the compressor will be sucking on a closed valve. If it is stuck open there will be no division between the hi and low side so the pressures will be almost the same. You are saying "binary switch' which should be on the high side line or on the dryer. If you loose your Freon it will shut off your compressor because Freon transports the oil your compressor needs. It sounds like you have a trinary switch, which has 3 or more terminals. You may also have a pressure cycling switch. You say it "literally stopped blowing all together", does that mean evaporator blower too? If you can show a diagram of your ac control system that would help. If you have an electric cooling fan make sure it works. If it doesn't your high side will climb over 400 psi and safe guards will shut your compressor off..