Hi, I'm new here. I have an issue where when I put my floor vents on, my defroster also comes on, but before everyone screams actuator, when you switch to dash vents the defroster turns off. Now I have checked all 4 blend doors. The main inlet, the temp one, the left main(dash/floor), and right main(defrost). I have removed them and manually operated the doors to verify that there is no obstruction. I ran the blower and was able to close the defrost and get it to just blow on the floor. I have watched the actuator move, now i have a feeling its not moving far enough. So I replaced all 4 blend doors just to be safe. Nothing has changed. When I flip the knob from floor to floor/defrost, I can see the actuator try to move but it doesn't. Its brand new and acts in the same manner as the original. I'm think the switch may be bad. Has anyone experienced anything like this and been able to figure it out? Also when I put recirculate on, the air blows twice as hard, not like a little harder, literally twice as hard. Fan speed remains unchanged. I have two other s197 mustangs and neither of them do this. Sorry for the long post, but I feel as if the details are necessary.