Climate control did not fix problem. Noticed the problem on defrost today to. Car running about an hour before it happened. I am wondering if the heat is causing the mode door to get stuck in a funky postion. I can hear the fan blowing and you can hear the difference. Its like its blowing into itself. You can change modes, but you just dont get the air volume. After the car sits off for about 15 minutes it fine. I had the car apart and tried to get it do it while I was measuring the voltage at the head, BCM and mode motor, but could not get it to do it for 1.5 hours. Hopefully it will happen on my way to work where I can check it not being in the cold. This is supposed to be the winter car for me. No defrost no can drive.