I have a problem with the motor for my suburban and it stems from this motor that I believe tells which vents to use when the controls are used by us to tell the truck which we would like.

It seems from my understanding that this is controlled from a part in the top of the steering wheel area under the area that shows your mileage. Maybe it went out and needs to be replaced. Mine gets stuck but still works, so I know I have to get mine replaced I just havent done it yet. Hope that leads to a possible fix for you.

I may have misused the term "motor" but that is what I assume that part is considering that mine gets stuck and I can hear the click in the back of the steering wheel area.