I have a 1990 190E. The Left Rear window was inop. I installed a new window regulator (it went in pretty easily) and it unfortunately didn't work. I tested and trouble shooted by referencing the CD-ROM, and I don't think it's a bad switch or wiring; I swapped out the switches and also applied power directly -- the motor seems to be getting power correctly. But it doesn't move the window up or down. For now I've left the new one in there. Any suggestions?
Thanks for your help.