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Lincoln Navigator
Plymouth Voyager
VW Transporter

How do you get the defrost to work in 1999 Lincoln Navigator?


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Wiki User
August 30, 2007 6:22AM

Two different vacuum actuators opens and close the mode doors to direct the air to the floor, vents, or defrost. Either you have a bad vacuum motor, or (more likely) you have a cracked vacuum hose. Crawl under the dash and listen for a sucking sound. Also, check all the plastic lines to see if they are cracked.


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