EDIT: PROBLEM FIXED. See linky
https://dodgeforum.com/m_774331/mpag.../tm.htm#774331

Repost from the 3rd Gen forum, but some of you guys probably don't visit over there much. I'm at a dead end.

2003 Ram won't change from vents to floor/defrost. I pulled the dash and HVAC unit and it seems that the dash vent actuator opens/closes the vent door to send airflow to the foot/face door. I tested all the actuators and they are moving the doors just fine. The factory service manual mentions performing HVAC control calibration but does not say how exactly to do it. Anybody done this before?

 

Sounds like you have a vacuum leak. That is what actually move the door. There is a TSB about this. I know it has been posted.

 

Nope, all the HVAC doors are controlled by 12v actuators. I found the TSB and figured that was the problem, so I ordered the parts listed in the TSB. Everything checks out fine though and the defrost door isn't broke. I guess I'll throw it all back together and try a new controller. Time to go buy more beer first. [sm=icon_guiness.gif][sm=icon_guiness.gif][sm=icon_guiness.gif]

 

Well I dug a little farther and found the problem(s). Link to info post up top.

 

WOW dude you ROCK !!! [sm=icon_rock.gif]

I don't have a 3rd gen, but the information and pics you provided are priceless !! Have a beer on me bro .... well done!!

[sm=icon_cheers.gif] [sm=icon_guiness.gif]