Hey Term,

I forgot about something. The switch that commands the central locking on a
W 124 is double. There is one plug with 3 wires : a mass, one to the electric
vacuum pump and the third to trigger the front or rear dome lights.
So how many wires comes out your switch ?
As there are a lot of W 123 T on this forum I am shure someone will know the answer to your question.

Danny