Need late W115 Turn signal switch

[daidnik]

The pot-metal piece with the cam has broken in at the end of the slot. I don't think further repair is an option.

The P/N is: 004 545 0824

This one has the 3-position wiper speed switch and looks like it was the last version on the W115 going to the end of the series.

I do find a couple of other variants used on the W114's:

004 545 3224; 004 545 7624 & 004 545 7524

I don't know what the differences are.

I'm interested if anyone has a switch that will work. Functionally the switch also has headlight dimming (forward/back) & momentary flash brights (all the way back against a spring).

I am familiar with the worn cam syndrome the requires filing to fix; been there several times.

Interestingly enough, among those P/N's cited above, price new ranges from ~$170 to $300. This makes me even more curious about the functional differences.

[barnumlives]

i'm holding the turn signal assembly from a 1975 240D in my hand and can't seem to locate the part number. this has the 3 speed twist wiper control (intermittent, slow, fast), the push forward for brights and pull for flashing the brights.

it needs to be notched for left hand turns, it holds the right turn position.

i had been considering putting it in my 1972 220d for the flash function. but if it is what you are looking for maybe we can make a deal.

[daidnik]

MB will mark P/N's on almost all the rubber parts, but not on any of these turn signals.

Well I did get the thing fixed (replaced) this morning, and I've figured out about 6 different variations of these things. Four of the variations can be spotted from the outside. These are:

Chrome stalk; 2 speed selection wiper (no intermittant)

Black stalk; 2 speed selection wiper (no intermittant)

Chrome stalk; 3 speed selection wiper (w/ intermittant)

Black stalk; 3 speed selection wiper (w/ intermittant)

The last two are more difficult to ID. These involve the contact config at the rocker switch at the end of the stalk which can't be seen from the outside; you have to remove the square handle at the end which is pretty easy to do. You drive out the ~1.2mm diam pin that is barely visible from the outside and runs thru the square handle and keeps it from falling off.

Anyway, apparantly there are some later versions that have two pairs of contacts in that end switch. This is the variation that I got from my friend Rudi who had a box of these turn signals. The only problem was the missing P/N's on all of these. Well the result of putting the dual contact rocker part in my car that was only supposed to have one pair of contacts was that it supplied power to the wipers in BOTH switch positions, i.e. the wipers could not be shut off. We didn't figure all this out right then, but I did a little later when I disassembled both units side by side.

What is totally amazing by todays design standards is that I was able to easily remove the single pair contact rocker end from mine and put it into the twin contact new switch thus removing the undesired 'auxiliary' power path. To do this I had only to push out another 1.2mm pin that acted as an axle for the rocker. The rocker for the wiper speed switch was also of the same design; easily disassembled.

So the good news in all of this is that these early versions of the turn signal switches with the cast pot-metal cam-slots are so rebuildable that the enterprising mechanic can make something work with a visit to the 'graveyard'.

In my case I actually got a new turn signal. Rudi has just flagged it years ago with a tag that said "Turn Signal Switch?" so he had probably run up against the same thing as I saw, we just didn't figure out the 'why' until today.

What amazingly workable designs! When I looked thru that box of turn signal switches, I was amazed at how many common parts there were in all of these. The only real differences have to do with the number of switch contacts, but as I said, you can mix & match these.

[79Mercy]

FYI, a W123 turn signal switch works on late model W115's.

[daidnik]

There are three variants in the W123's alone; none of which cross to W115 according to EPC.

A person would have to either brilliant or a complete fool to order a new switch from MB at a cost of $200-$300 and not follow the cross-referencing to VIN.

Now the realm of the recyclers is an entirely different matter. That is a cult-like group who learn by trial and observation about functional design differences and convey these details to their fellow cultists. Presently I find myself in this group and thankful for today's results.

[79Mercy]

No, of course the part numbers are not the same. Remember the W123 switch will always have atleast an extra pin because 123's have the windshield washer pump, W115's have the foot pump.

I removed a turn signal switch from a wrecked W123 1983 300D Turbo and put it in my W115 1976 300D and it works great. No reason to hunt down the ultra rare 73-76 W115 switch when a W123 switch works fine and its MUCH easier to find.

[daidnik]

According to EPC, that car has two variations: 004 545 3224 & 004 545 7524.

Neither of these used in my '73 220 and the W123 300D & 300TD use yet other variants that are different.

I don't dispute your success with the part, but this in one area where EPC is not very helpful. Indeed, if the bag or box was opened on these things and became separated from the part, you would pretty much be on your own to figure out what vehicle that switch was supposed to work with. I'm pretty sure that's how the new one I found today got into that box and had probably been there for at least 15 years or more.

Another interesting note on the matter of "pins" is that all of the signal switches I saw in Rudi's box had that same 14-pin connector.

Another minor electrical difference I have noted in the new switch I hybridized this morning is that with my old one I could flash the brights even with the ignition off. With the new one, the ignition must be ON.

[Algebrat]

I have a 300D that the turn signal won't go up, for the right signal. It previously had the won't stay engaged problem for both directions. I have a parts 1976 300D with a functional turn signal that has the same, won't stay engaged problem. Here are my questions.
1. I have found a website with a new 123 switch for $68. I think I could make it work, but I am curious, did they correct the won't stay engaged problem in the 123 switch?
2. If the engaged problem can be cured, I think I would probably fix the one from my parts 300D. Is it possible to correct that problem?
3. What is the trick to getting the rubber cover off? Do you remove the cruise lever?
Thanks for any help.