Ok, I know everyone is tired of reading the heating questions, so am I. I have read post after post and checked "everything" that has been recommended. My problem is with the defrost only. Everything works until you hit defroster and nothing comes out of the center vent, but, comes out of the defrost side vents. IF I turn the speed level to low and move it to floor, the floor works and a little warm air comes out of the center defrost vent, but, if I turn it to the next speed up, you hear a flap shut, and then floor only. In Indiana, I really need the defrost bad. Thanks for any info or tips that you may have for me.