Thanks for your question. Sorry you're having car problems, I will do my best to research this and supply you with an accurate answer ASAP. The vent blend door in the heater box under the dash is either stuck or broken, that's what causes that to happen. Hope this helps you. Thanks, Ron
The problem lied with the climate control module - had to replace. Vent blend doors are fine.
I see, thanks for the info. Ron