The clutch doesn't engage at all when you hook up a jumper to both terminals of the cycling switch harness? I haven't done to much testing of my compressor before, but did you check to see if the harness running to the compressor is getting power? If it is, i don't know where to test it from there to see if it is bad.
if the plug that plugs into the compressor is getting power when you jump the low pressure switch, but the compressor clutch isn't engaging, then the clutch is probably bad. The clutch is pretty easy to change, but it cost about as much as the entire assembly!!
Last time I checked, the clutch gets 12 volts and ground. The 12 volts it gets is after all of the pressure switches - if you have 12 volts and ground to the clutch, the rest of the electrical is up to par enough to engage the clutch.
I would check the tolerance in the clutch to see if the electromagnet force can lock it up.
If you can post what it's doing, the smart folks in here can probably help a little more.
Well, i retested and the refrigerate was low (this is on my 94 Ford Ranger). I knew the system was the same as the Mustang so that's why I asked here. Again thanks