Having problems with your 2006 Chevrolet Trailblazer ?
Trailblazer vents wont change from defrost ,to your feet,to your face etc. 2004 just had air compressor replaced if that matters.
System uses vacuum to operate the doors. Defaults to defrost when vacuum fails. Vacuum line from engine intake manifold is probably off or perhaps leaking--may have been disturbed during the other repair work. look for small loose vacuum line in engine compartment.
Repair Help & Product Troubleshooting for 2006 Chevrolet Trailblazer
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