ive had issues also,no matter what button i push air comes out of all vents heater,defrost,side vents,except the 2 middle vents of course they need to be set to e/c on a/c. but,have you checked the temp sensor on the ceiling above the rear view mirror,or checked to make sure the return fan behind the passengers vent is working correctly it monitors the air temp of the automatic climate control.good luck

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