W108 3 wire to 2 wire window motor wiring

[ryanougrad]

I have a 68 280se with original 3 wire window motors. I need to convert them to the 2 wire as I have not found any 3 wire motors but multiple 2 wire motors. Does anyone have a copy of the bulletin Mercedes released on how to do this? I know it involves some relays. Any help would be great.

[Idle]

Something that might help if you cannot find the real answers is that the three wire systems, at least the ones I have worked with on US cars, involve one ground wire and one wire for one direction and another wire for another direction. In other words, the command for up or down comes through the make-up of the switch which throws current to one direction or another by throwing 12v + to one wire or the other with one wire always being the ground.

The Mercedes two-wire system reverses the polarity inside the motor so in one direction the motor is up and in the other the motor is down by changing which wire is + and which is (-) inside the switch. This is the simplest method of changing the direction of a DC motor, and simple often means more durable.

Not that this will really help except to let you know what you are dealing with.

[801mbz]

I may have some old 3 wire motors. Call 801 706 6871.