My air was going out intermittently this week and I was about to take the truck to the dealer but did a little research on this site. I found a thread about the electrical connection behind the dash being loose and that fixed their problem. Well, I removed the dash radio plate cover and re-seated the electrical connections for the controls and viola!, it's working again. I can hear the compressor cycle as soon as I hit the AC button, which wan't happening before. I realized I had been doing some off roading last weekend and that probably shook the connection loose. Thanks for this great website and the wealth of info you can find on here, it's the first place I go when I have any problems with my Cummins(which isn't much other than a rear main seal covered under warranty). Thanks again!