PeachParts Mercedes-Benz Forum - View Single Post - Late-124 convenience modules

Jeremy5848 · #8 07-27-2009, 08:04 PM

[after a little research in the 1993 electrical diagrams] The auto-close function in the '93 300D 2.5 and similar models uses a "convenience control module," referred to in the schematics as N57, which lives under the rear seat on the left side. All of the window and sunroof wiring runs through this module, which is part number 202 820 09 26. I haven't priced this part yet but expect it to be very expensive ($ hundreds, at least). A junkyard part would be a better option; at Pick and Pull it would be a "large relay," about $30. I have seen several but didn't know what they were at the time. There is also a "convenience" relay in the fuse/relay box that is part of the circuitry.

The real challenge would be rewiring the electrical system. If one had a late-124 junkyard car from which one could strip parts as needed, and one was taking the interior of the early-124 out anyway (to update to the later style, for example) it would be possible although a lot of work.

It is unlikely that a simple home-made modification would allow this "convenience" function to work in an older W124. This is unfortunate. Perhaps a simpler version could be cobbled together to operate one "most needed" function, the one that you're always forgetting (close the sunroof, maybe?). Let me look at the 1987 schematics.

Jeremy