W212 wiring diagram

[Justintyme]

It’s over 40 years since I did this but iirc it should be black to left taillight and brown to right taillight.
Functionally no different but it could get confusing if you have a problem and are trying to diagnose a problem

Well, 40 years ago ( and yes, I remember them too.) And up to recent times, 2010 in my case, it was simple enough to wire a trailer, using a relay.1 function, one wire. No problem. But now in my 2014 w212 Eclass, the brake and park lights are fed by a single cable. And try as I might, my so called Smart Relay, is unable to differentiate between the two, and send the voltage to the correct brake or park bulb..technology

 

[Justintyme]

Hi, sorry for the confusion , yes its a saloon as you had seen in the picture, and you may be right and the method you mentioned may be the right one for you.
Good luck.

Thanks again, you have been most helpful Take care with your cycling.