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post #1 of (permalink) Old 04-23-2001, 08:20 AM
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Problems with vent knob

Hey Guys,
My vent knob seems to be stuck in one mode, defog. When I turn it to Vent, nothing's OFF or Defog. Is this an electrical problem or mechanical (broken cable)? Any pointers would be appreciated.

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post #2 of (permalink) Old 04-24-2001, 11:15 PM
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Re: Problems with vent knob

Sounds like a vacuum problem. The only cable on the HVAC system controls the cold-hot temp. Pull the control off and you'll see a vacuum harness that plugs into the back of the controls. In the controls there is a sliding disc that directs vacuum from 1 of the hoses to open the different doors inside the dash for defrost, vent, A/C, off, ect. Make sure all the hoses are hooked to the controls and that one of them supplies engine vacuum to it. Good luck with it.

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