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Why would your vents blow air through the defroster but not through the dash?

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Answered 2011-09-13 17:27:42

Some of the air handling dampener motors are vacuum controlled and some have a small electric motor. If it's a vacuum controlled dampener, you probably have a vacuum leak, faulty vacuum diaphragm or disconnected vacuum line. If it's an electric dampener motor you have a bad connection, faulty feedback switch or faulty motor assembly.

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