It sounds electrical to me too. It's plugged in at the compressor, and the plug in the pressure switch is in. I cleaned the contacts on both too. Where are the rest of the electrical connections for the compressor? Is there a fuse or link or relay?
I'm concerned about the high reading on the low side, even though the compressors not running, doesn't make sense to me. BTW, it's r134a, not freon, I should have been more specific. I had it converted 3 years ago when the compressor and condenser were replaced.