A recent posting commented on "cheap" eBay window switches. IF your switch is erratic in function, try this:

Pry off the top (part that rocks up and down), and put a drop or two of either Corrosion X or Corrosion Block (well, you may have to buy it first!!) on each of the two copper pieces that are just below the top. (needn't remove the switch system from the console, but it is helpful if you pry the
block portion up from it's normal mounting position). Then, snap the top of the switch back onto the block and I doubt that it will ever malfunction
again. Done it with several different switches on the cars and it always returns to like new functioning. The drop runs down the copper into the
contacts and cleans off any corrosion that is interfering with the electrical contact.

Actually, using either Corrosion X or Corrosion Block on EVERY electrical device/connection in a 928 as suggested by Earl Gillstrom may be the best way to eliminate electrical problems for YEARS.

Gary Knox
West Chester, PA