My '95 C36 has the newer power seat switches, where there's small square modules attached to a circuit board. I've tested, and found that the seat switch is indeed the culprit. Tried spraying contact cleaner through the modules, no change. There's plenty of info regarding the rebuilding of the old style seat switches with the little bars and balls, but not much on these new ones. Am I stuck buying a new one for $130, or can it be cleaned/rebuilt?

Switch in question is 202-820-07109051, shown here:
http://catalog.***************/********az/detailw.jsp?sid=ogfyg4554q5ids55c0frmoft&partner=********az&product=202-820-07109051

Take it apart, what have you got to lose?

To answer my own question, yes they are possible to clean. Once you get to the little modules, the top will snap off by inserting a screwdriver in the notch on each side. Once open, it's easy to see where the electrical contact is made on each side when the lever is moved. I cleaned each side of the contact with sandpaper then sprayed it out with electrical contact cleaner. Between my two seats I had 4 different functions that didn't work, now each one does. Considering a new seat switch is $130, it was definitely worth my time.

If you have to use sandpaper, I'd use 2000-3000 grit, and VERY sparingly. If the contacts are plated with precious metal, you can bet that that coating is a few microns thick. The corrosion is more likely ome kind of spillage or contamination - even electrical grease that has attracted dirt and dust over time.

I crack up when I read that people think that they can make a fortune melting down old CPU chips like pentiums for gold. I read that National Semiconductor, a multi-billion dollar company, uses less than a pound of gold in a year in chipmaking. That's how fine the wires are and how thin the deposited gold is. Now, in pre-1975 computers, maybe another story.

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The contacts appear to be garden variety brass, though I suppose they could be plated with something. I would guess that they were probably suffering from a combination of dirt and corrosion. I agree with using a finer grit paper, good luck cleaning electrical contacts with 60 grit.

hmmm, I took mine apart ('91 W124) and thought it was hopeless compared to the older style ball and "seesaw" style. It appeared to make good contact and didn't see anyway of repairing it. I wonder if the plugs can be changed to interchange them. I'll reopen it and clean mine now, thanks.

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That was exactly my thought. There's a lot of information available regarding the old style switches, when I saw that mine was full of little boxes I figured I was SOL. Then a forum member send me an email saying that they were cleanable. I figured what the heck. All that I cleaned now work like new.

Mine also seemed to be working ok, and making good contact. All I did was insert sandpaper between the open contact points, lightly hit both sides, then rinsed with electrical contact cleaner. I'm thinking that there was a light buildup of corrosion or dirt, because when I was trouble shooting I would see 0.3 V going through the switches in question. Obviously it doesn't take much to prevent them from passing a full 12 V.

Any more details you could give me on that Audi powered 914? As the former owner of a 951 and '70 911T, I love to see an interesting Porsche.