My 2000 e430 rear windows do not work. I bought the car in this condition. I started messing with the driver side window and it fell into the door. I had the unit including motor replaced. This fixed the window now locked into closed position but not the power. Light tested leads in the door and nothing. I then took center console apart and completely took apart the windows control unit and cleaned it. Still nothing. Light tested switches on board. Nothing. I went to junk yard and got 2 of these units and plugged them in and still nothing. Only the front windows work in all situations. Could all 3 units have been faulty? A new piece is pricey.