Originally Posted by
Sussudio
Yeah that's my current problem, no engagement of the clutch while turning on the AC. I'm probably going to have to eventually have someone look at it. I've tried almost everything it seems and no progress and still no hard evidence on what's the root cause. Quite frustrating as I usually able to fix mostly everything on my car, but AC/Heater systems is the least of my knowledge. Hell I've felt like I've learned a hell of a lot more about it though in the last three days than in my 21 years of driving lol.
Inside the black plastic box that holds the RCM, PCM and BCM there is an electrical connector mounted on the front of the big box. That connector is for the AC compressor. You can bypass the control module input/safety limits and test the compressor clutch by directly applying 12v jumped from the battery directly to the compressor at that connector. If the clutch engages you know it is a safety switch/low pressure problem or control module problem. If the clutch does not engage then it is the clutch compressor problem. I've forgotten what color the wire is, but you can see it in the wiring diagrams in the service manual.