When I replaced the center console in my 1990 500sl, I got a double bonus. Before reinstalling the switches I cleaned them up a little. While testing the connections before I put everything back together I had a pleasant surprise. My passenger side window was now at “normal” speed. Even the laboring noise was gone. In the five years I have owned this car they were always slow. They were so slow that I always thought at some point I would have to do a repair job on them. Coincidence? Maybe. Sometimes you just have to get lucky. It is the first time in $8000 that I have used luck and repairs in the same sentence with this car.

BTW, thanks to the poster for the console installation procedures. It makes things sooo much easier to see something done , then do it.