I put up a request for this, nothing yet. But I have a proceedure that may offer limited success.

I have a spare switch that only intermittently worked on a few functions, but mostly nothing. The switch seemed physically ok, nothing broken (the paddle joystick needed to be glued on) but it was gummed up electrically. This unit sat in my car before I saved it and was rained on for years with no drivers side glass installed.

All I did was soak it for 5 minutes in Tarnex. I drained it and then soaked as much WD40 into it as I could to help displace the remaining Tarnex. Finally I cleaned it thouroughly with paper towels to get as much WD40 off the surface as possible. Now every function works.

Everyone may not be so lucky, so if someone has ever had the switch apart - chime in.