This is the 99 in my sig. Up to now, it's been a minor problem. What happens is that EVERY vent is open, and I have no control. The problem is, early morning, I want my windshield defrosted before I worry about my feet. Yet, my feet are sweating and I'm looking out the tiny window on the windshield my defrosters made. I don't even know how to start troubleshooting this......

 

Your vent door might be controlled by a small electric motor. There is a common issue with them I believe. I'm sure someone who has had this issue will chime in shortly

 

Check this out and watch the associated video on a possible repair for the blend door.

http://heatertreater.net/dodge-ram-95-02/

 

The blend door doesn't control the vac actuators. You probably have a bad check valve or not enough vacuum. The main check valve is on the passenger side of the kegger. If you don't have the second check valve get one from napa(part#730-1349)

This may help.
http://dodgeram.info/tsb/1996/24-01-96a.htm

 

Or a vacuum issue. Check out "wild vents".

 

Wild vents, or, lack of vacuum, will have the airflow directed thru ONLY the dash vents. (Defrosters) Since EVERY vent seems to be open, I would more suspect that the control head is faulty.