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What has happend is, inside the Control Module, on the back side of the knob, there is a little metal box. On the flat surface, you will notice that there are 4 lead type rivets in the corners. Well, over time, these rivets become loose, and that metal that goes around is actually a ground, looses contact. So. There are 2 ways to fix your problem. One is replace the entire HVAC Controls, or take it apart, and (what I did on my 96 with the very same problem) you can take a pair of LARGE pliers, and smash that lead piece back down tight. Now of course this is only a temporary fix, but so far on mine, its lasting.

Anyways, I'm almost 99.99 percent sure this is what the problem is.

I hope this helps you. If you have any more questions or need any more diagrams, please don't hesisitate to ask...Thanks again, JHoop
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