W123 "Mystery" Window Switch Layout
 

I have four wagons in my shop: my '82 daily driver, a 1980 being converted to a turbo-stick,
a customer's 1983 "greasecar" conversion, and a 1985 for parts.

Unlike the other three, the 1983 has aftermarket window switches, the kind
that sort of "explode" when you try and service them, and thereafter -- plastic
housings and metal tabs, everywhere. The replacement switch is on the right.

http://franklynb.home.mindspring.com/_617/00002-m.jpg
I'd like to restore this car to original window switches, like the one
of the left, above.

BUT, the pin plugs are a different size! AND the orientation of wires in
the housings differ. Even the number of connectors on the back of the
switches is different!

http://franklynb.home.mindspring.com/_617/00001-m.jpg

I've looked in EPC, but there is no record for any "one year special",
using a different switch and harness layout that I can find. I haven't torn the seats out,
but here's my question:

* Did these aftermarket switches come with some sort of sub-harness
that adapts the switchgear to the smaller pins -- and layout?

I see no evidence of a sub-harness, but haven't gone "inside the console"
to check further -- yet. The only record EPC shows is the switch on the
left: A 000 820 82 10.

I sorta doubt that M-B would change pin sizes from the "standard" 4mm.
I can't find a 1983 wagon schematic, but the 1980 and 1985 are substantially
the same circuit, unike what I'm seeing in this 1983 "weirdo".

Ideas?

The ones with the silver surround look like the ones in our '79 which are stock, while the black ones match the '85, so it looks like your '83 has the early switches installed. I haven't pulled mine to check the pins, though.

An '83 should not have the early style switches with the chrome trim. As you note, they aren't interchangeable.

I can only offer as a WAG that either the car came with wind-up windows and someone converted it from an earlier parts car, harnesses and all, or it's got the wrong year on the title or been re-VINed, etc. The chrome switches are the style from 116s, and early 123s.

If memory serves, the center console wood trim is different on a car with the newer-style switches, as well. (The black switches fit into a smaller opening.)

The '83 with the chrome switches: is it a 240d or a 300d?

As you note, for sure no one intended these switches to be cleaned by the hand of man. Though some people have succeeded (my hat is off to those intrepid souls... I just gave up and bought more used).

Its a 300TD. Since its a turbo, has the correct heat shields, a manual sunroof,
and a 722.3 transmission, I sort of doubt its a re-badged earlier car.

I double checked for a "sub-harness" today, and cannot find any support for
a second connector between the plug under the ashtray, and the point where
the harness submarines under the side console carpets.

Tomorrow, I pull the console to get a look at the layout of the plug. If it matches
the 1983 wiring diagram, I'm stymied! The biggest question: how does one implement
the wiring strategy with fewer connectors???

Whoever told you the replacement switch is the chromed switch, is incorrect.

The chrome trimmed switch was in production until 1981 model year. In 1982 the illuminated switch replaced the chrome trimmed switches. In 1983 the electric adjustable passenger side mirror became standard.

If the chromed replacement switch was on the '83 car then the center console was replaced since the earlier style switch is larger and has different plugs as you observed. If it is automatic transmission the PRNDSL shift gate is positioned differently as well.

I just got back from the Pick and Pull with the updated switches for my 81 300d because the chrome ones have driven me to drink. And to safety wire the thing together.

I logged on here and was looking for answers, not questions :D I'm guessing the extra pin on the updated model is for the light. Did you make any progress before I bust out the volt meter? I did notice that the updated switch is longer and we'll require modding the console. Should be worth the effort since the switch is so much better quality.

Comparing wiring diagrams, it looks like the difference is for the light bulbs. Post #21 in this thread has a wiring diagram that should match the chrome switches (8 pins, no lights) http://www.peachparts.com/shopforum/diesel-discussion/300430-power-windows-83-240d-2.html?highlight=sausage

The other wiring diagrams have an additional wire for the lights. This will only be hot when the headlights are not in OFF. It may be one each hot wire, for a total of ten for the black switches, or it may be an additional ground. The diagram doesn't show a tenth pin. I would think it's an additional hot wire for the bulb based on the drawing of the switch, but can't say for sure. The two pins may also be one hot and one ground.

The upper groups top center and the lower groups upper left (in the photo) appear to the be the "extra" pins. The metal strip from the top center to the corresponding position makes it appear that performs the same function.

The two triangle groupings are then similar between the chrome and the plastic.

Thanks for the comprehensive response, Yak. I think I need to go back and get the updated plugs to go with the switches. Or, I could just use electrical tape like the PO and carry a bunch of fuses.

There may actually be some form of "sub harness" in the console. From the '81 wiring diagram with the unlighted switches it describes the C107 connector (underlined numbers in the pdf) as a 6 pin connector and the C108 connector as a 2 pin. This would provide the hot and ground wires for the switches (4 + 2) and lockout connector (2). So the other side of C107 may have connected to the backs of the switches. In the later versions C107 is described as 8 pin.

It's possible it goes something like this:

Fuse box/chassis ground >>>> C107 >>>> backs of switches

and

C108 >>>> backs of switches.

If you can find where C107 and C108 plug in maybe you can get a plug-n-play install.

Plug and play would be best, as then you could hardwire at the sub harness.

Finally had a chance over the weekend to stare at it and the pins on the newer switches are actually larger than the old chrome-don't-get-you-home switch.

I wonder how this project turns out. I think changing the pins on these is easy. If the whole harness swaps.... even easier.