:Here is the back story. My a/c went out completely, nothing worked, just hot air. I had it diagnosed by a local reputable shop and was told that the compressor had disintegrated and that there were metal shavings throughout the system.

So, I got the bright idea that I could change out the whole system and fix it myself. My buddy and got it all done after about 3 weeks of working on it on our spare time. Our biggest conumdrum was what the D and S meant on the compressor. After some research, a phone call to the dealership, I was told the the D was for discharge and it was the high side and that the S was for suction and the low side. After all lines were hooked up, PAG oil put in the system, and R134a put in the system we figured we had it licked.

But no , For some reason the compressor does not want to kick on. Remember this is a new compressor. We jumped the compressor and are able to get to engage and work but hooking up to the OEM wiring does not work.

Today I changed out the relay under the hood and nothing happened. I am stumped. Any ideas are appreciated?
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Next thing to check after that is your switch. Have you jumped the compressor on past the relay? or before the relay? If you've jumped it before the relay then it's probably your switch that's bad.

Are you speaking of the switch on the dash? If so, how do I check that?

low pressure switch. on or near the accumulator. unplug it and jumper the switch, see if the compressor kicks on. Did you vacuum the system before filling?

Yes, vacuumed the system then PAG oil, then R134a, and of course we were careful to put in the right amount.

What Matt said, if you had black death in your A/C system, that switch must be replaced. Didn't think of it cause I guess I figured it was replaced when you replaced everything else...