The AC started blowing hot air in my 05 KJ 3.7. My first thought was a refrigerant leak.
I hooked my manifold gauges and jumped the low pressure switch to get a reading. The clutch did not engage. I tried throwing parts at it and replaced the AC pressure transducer hoping to get lucky. No luck.
I have checked continuity on all of the AC related wiring I can think of.
I can jump the AC clutch relay and every thing works as it should. AC blows cold and pressures measure perfectly. The relay itself is not the problem as I am not getting voltage in the proper relay prong slot to energize it. Something is not telling the relay to turn on when it should.
I have had all the fun I can stand for this holiday weekend. I hope you all enjoyed the fourth!
If you have any ideas I thank you for your help. MBanning

Sounds like you have already checked all the important stuff.
Time to start looking for a blown fuse or a bad switch on the control panel.

_________________
U.S. Army Retired

Thanks Flash.
Fuses are good. I forgot to mention that in my first post.
I'm not sure how to check the switch on the dash but I will do some looking.
I had ruled out the dash switch because I think the windshield defroster will also cycle the compressor clutch when it is working correctly. It will not work with defrost now