How to Remove a W126 Window Switch

1. Pop your the hood and remove the negative battery cable with your socket set.
2. Use your Phillips screwdriver to remove the two screws inside the arm rest on the door you'll be changing the window switch on.
3. Lift the top of the armrest to expose the window switch. A small plastic wiring harness is attached to the bottom of your old window switch. Squeeze its ends together and unplug the wiring harness from the switch, then take the switch out by hand.
4. Set the new W126 switch in its place and plug the wiring harness into it. Set the armrest back down into position and also replace the screws that held it in place.
5. Replace the negative battery cable.