1996 jeep xj, I just replaced the entire AC system as I live in TX and the wife was not happy. I have power at the solenoid and if jumped it will work, same for the aux fan which I have been having problems with not working and have replaced all the parts to it including the fan if I unplug the temperature switch it does kick on. When I turn the AC on the engine does not change idle and the clutch does not turn on unless as I said I jump at the solenoid same also goes for the fan if I jump the solenoid it works. When you first plug in any of the solenoids the fan and/or compressor will turn on for a half second but otherwise will not run I have already tried multiple other good solenoids still does not work does anyone have any ideas on what could be wrong. As I said I replaced the entire system condenser evaporator all the hoses compressor low high safety switch etc.

 

The high and low pressure switches send signals to the PCM. The PCM itself grounds the coil side of the relay (which I'm assuming is what you're calling the solenoid) to engage the compressor. Older vehicle ground points are often neglected, and are a likely culprit. There are many writeups on how to clean them up. It's easy and free, so I'd start there. If the AC still doesn't work after that, take a look to see if the PCM is calling for the AC to come on (use a test light and verify ground at the coil side of the relay).