I HAVE A 2003 CHEVY SILVERADO. THE HEAT/AIR OUTLET CONTROLLER WILL NOT CHANGE POSITION (FLOOR, DASH, DEFROST, ETC). I WONDER IF THIS WOULD BE DUE TO A BLOWN FUSE (I CANT FIND ONE) OR MAYBE A VACUUM HOSE LEAK? OTHER SUGGESTION?
The problem might be with the mode door actuator which has a logic control board contained within, or the HVAC control module which is the component on the front of the dash with all the HVAC controls.
The HVAC system is electronically controlled.