[Jsmith03Cummins]

I had that problem, if you have an adjustable steering wheel try moving it up an down. The power wire to your fan connects right where the steering wheel adjusts. The wire will work its way out over time. Until you get it fix you can just move it up an down until it works. Seems to work best the higher up the steering wheel is

 

[chood45]

I had a problem with my 06' back in the summer. It quit blowing cold air. Took it in to the dealership for warranty and either the blend door, or something inside that part of the dash had broke and was not allowing any air flow through the vents. I'm not for sure if you meant your fan isn't working electrically or not flowing any air. Hopefully it's not what I had cause I'm sure your's is out of warranty now like most of us who have 06' models. They had to remove most of my dash to repair mine.

 

[cummins_smoke]

I have an 05 cummins and had a problem with it not blowing all the time but some times it would. got on nhere and asked a few questions and found exactly where to check. It was the main wire harness next to the steering column on the left hand side. from tilting the wheel so much it caused it to make a weak connection and fry the wire harness. Was not to hard to fix did it all my self.