I hope this in the right section it is in the interior so i figured....? Well I’m having trouble with my ac/heater. I have the dual climate controls in my 04 GMC. I have been told by gm three times cause they have tried to fix it three times that the "flapper door" under the dash that switches from hot and cold gets stuck in one position or the other. Over the summer it got stuck on the heat side and blew only hot air and not it’s on the ac side and is only blowing cold air. What can I do to fix this besides taking it to the dealership? Reason being as if I take it back to gm I’m going cry lemon law! Which I don't want to do, because I will loose all my work that I have put into it. Help me out guys. Thanks for any help.