Sounds like you have a problem with your vent control levers. Your truck likely has an electic controled actuator at the dash that signals the switch. Look into the path the vents take. Where is the junction from dash vents to defrost vents. The all come from the same place, the cooling fins behind the dash. You may need to repace the electric switch in the dash. It could be clogged, of a manaul lever broken. Taking off the dash should narrow it down.
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Wednesday, June 25th, 2008 AT 9:18 PM