Of course it's hot as blazes now. AC hasn't worked since I got the car, but wasn't too big of an issue til now. Anyway, to the point. Compressor is not locked up, but will not energize. Replaced the pressure transducer, hooked up ac can with gauge, and compressor never turns on. Check fuses, good. Check relay, good. However, I have found the culprit, and here is where opinions are requested. I don't have +12V at pin 87, so when the relay closes, there is no voltage to turn on the compressor. I had voltage at the fuses, but pulling the relay out, there is not 12 volts on the fuse block unless I wiggle the test lead, then sometimes I get it for a bit. Reinsert relay, and it goes away. I'm suspecting a loose connection in the fuse box, but accessing the back is a total PITA. Thought about running a fused 12 volt source to pin 87 of the relay and then jumping it to see if the compressor will come on. I do have the Lisle relay tester, which makes troubleshooting a lot easier.
Pretty sure I'm on the right track with this, looking for confirmation and opinions.

 

You could be on to the problem, loose connection. I helped a friend with an 06 Impala (which matches the 06/07 Monte) and a rear defroster issue. We removed the fuse panel after we found wiggling things resolved the issue. Once the panel was out of the car, did what you are not supposed to do and pulled the panel apart. Where the relay connected in the panel, we had to squeeze the connector a little tighter, re-assembled and re-installed, problem solved.

 

It looks like the fuse box comes apart, but I can't figure it out yet. I might go to the junkyard, pull a box and experiment there. I was wrong in my pin number though, I believe it goes from 30 to 87 when energized. so, no voltage on pin 30. But, you knew what I was talking about. Thanks, I'll keep posted on things as I get to them. Being on travel again, I don't get to work on it as much as I like.