OK, I'm missing something basic here.

Background info: 1985 300TD-T.

A week or so ago, I noticed the left rear window wasn't working. I swapped out the console switch with a spare. That switch made it go down, but I needed to hit the rear switch to make it go back up. On the test switch, the driver's front window wouldn't work, so I put the rear window up and reinstalled the original console switch, and ordered a replacement.

While waiting on the replacement, my wife informed me that the driver's front window suddenly stopped working.

Got the new switch, and it fixed neither problem. Got to checking around, pulling the door panel, etc. and had power/ ground in all the right places at the right times. Pulled the motor, smacked it. it started working for a minute, then stopped. Pulled it out and apart- corroded inside. Ordered another one.

Driver's rear window- I have power all over, but flicking the switch either way only grounds the motor so it will go UP. I went to pull the rear door switch on the other working rear window to test it on the one that wouldn't work. Couldn't get it out of the surround. Then, suddenly, THAT window started exhibiting the exact same same symptoms- both up and down modes grounded the same side of the motor.

Ordered two rear switches, and another console switch for the left, just to be sure.

Got the parts today. Installed the LF motor, and that fixed that issue. Installed a new RR switch, and that fixed THAT issue. Installed the new LR switch and new L console switch... no workee. Same thing as before- both the console switch and the rear door switch ground the same side of the circuit in both directions, and the window won't move.

I discovered that the brown wire in the rear switch plug had no continuity to ground. So, I used a jumper wire to ground it, and that makes the window go UP but not DOWN.

I have power on both sides of the window motor as I should, but I can only make the window go up. I pulled the new switch on the right rear window to test it on the left rear. No change. The switch for the left rear works fine on the right rear window.

I'm using a W123 wiring diagram that has no bearing on this car- must be the first design and a W126 wiring diagram that seems "close", and everything looks correct. I just can't make the damn thing WORK! Does anyone have the correct diagram for a late 123? Any suggestions? Run into this before?

I power the window motor manually and it goes gangbusters in both directions.

Any ideas?

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1968 230S Automatic, Elfenbein
1975 O309D Executive Westfalia Camper Bus, Blau/ Weiss
1972 280SEL 4,5 Dunkelrot
1966 VW Type 34 "Grosser" Karmann-Ghia
1963 VW 1500 Variant Pearlweiss
1969 VW Variant Automatic, Perugruen
1971 VW Squareback Automatic, Clementine Orange
2001 E320 4Matic Wagon- Our belated welcome to the 21st century! Polar White
1973 280SEL 4,5 Sliding Roof "The Bomb", Dunkelblau.

Could be a harness issue. My drivers side rear door window has been unplugged from the main switch since I found out the blue wire was giving 12 volts to the instrument cluster when i use the switch. It took out my cluster. Look inside the rubber accordion thingy in the door hinges. Maybe its just there. Mine is somewhere between the hinges and switch. I havent fix it yet.

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'85 300D Cal 280,000 miles
'14 GLK 350 60000 miles

I have power everywhere, and my problem seems to be grounds. The wiring diagrams really aren't clear on where the windows ground, or thru which wires, or which contacts the switches actually make in up and down mode.

Your problem sounds like someone got the wires in the wrong spot on a switch- OR maybe yours was trying to ground through the harness to the cluster.

Am going to pull the well worn but working OEM console switch out of the '82 today and see if that fixes anything. The fact that these non- illuminated aftermarket switches actually DO illuminate when the switches are depressed and the safety switch is unplugged is spooky.

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1968 230S Automatic, Elfenbein
1975 O309D Executive Westfalia Camper Bus, Blau/ Weiss
1972 280SEL 4,5 Dunkelrot
1966 VW Type 34 "Grosser" Karmann-Ghia
1963 VW 1500 Variant Pearlweiss
1969 VW Variant Automatic, Perugruen
1971 VW Squareback Automatic, Clementine Orange
2001 E320 4Matic Wagon- Our belated welcome to the 21st century! Polar White
1973 280SEL 4,5 Sliding Roof "The Bomb", Dunkelblau.

Annnnnnnd... I pulled the old OEM switch out of the '82, plugged it in, and it fixed it... two- count 'em, two BRAND- NEW AFTERMARKET SWITCHES were defective right out of the box!!!

Why did I have two?

I bought the first one from my regular parts supplier and it fixed neither window. Also, I noticed that it didn't light up with the lights... so I ordered a more expensive one from an eBay seller that advertised it as an OEM illuminated switch... and it didn't light up, either. Seems they "forgot" to "update the ad"... grrrr.

Gotta love parts!!!

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1968 230S Automatic, Elfenbein
1975 O309D Executive Westfalia Camper Bus, Blau/ Weiss
1972 280SEL 4,5 Dunkelrot
1966 VW Type 34 "Grosser" Karmann-Ghia
1963 VW 1500 Variant Pearlweiss
1969 VW Variant Automatic, Perugruen
1971 VW Squareback Automatic, Clementine Orange
2001 E320 4Matic Wagon- Our belated welcome to the 21st century! Polar White
1973 280SEL 4,5 Sliding Roof "The Bomb", Dunkelblau.

Don't throw the old Mercedes switches out! Take them apart and clean /lube the contacts. They'll be good as new.

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85 300D turbo pristine w 157k when purchased 161K now
83 300 D turbo 297K runs great. SOLD!
83 240D 4 spd manual- parted out then junked

I chased this scenario before on the SD. A brand new aftermarket switch would not work and an old OE switch will work.

This was procured from a decent supplier, however no discussions with the supplier could get the problem resolved back to the manufacturer. The switch was not defective from a manufacturing standpoint. Their logic for continuity across various pins was erroneous and I'm positive that every switch they made would not function.

Sad sign of the times..............

Also, when you are in the PNP yards, remove the rear door window switches from W123, W201 and W126, (first gen). pop off the rocker part and use it for the front switches when the logo get worn off.


Charlie

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there were three HP ratings on the OM616...

1) Not much power
2) Even less power
3) Not nearly enough power!! 240D w/auto

Anyone that thinks a 240D is slow drives too fast.

80 240D Naturally Exasperated, 4-Spd 388k DD 150mph spedo 3:58 Diff

We are advised to NOT judge ALL Muslims by the actions of a few lunatics, but we are encouraged to judge ALL gun owners by the actions of a few lunatics. Funny how that works

One was a Meyle and the other a Uro, both from different suppliers. My logic function took over when the switches both ILLUMINATED with the child switch plug removed and bridged as a test. This tells me the switch is configured incorrectly.

I think ALL of these switches are now products of the Sum Ting Wong Mfg. Co. ...

On a side note, the aftermarket rear door switches seem to be OK.

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1968 230S Automatic, Elfenbein
1975 O309D Executive Westfalia Camper Bus, Blau/ Weiss
1972 280SEL 4,5 Dunkelrot
1966 VW Type 34 "Grosser" Karmann-Ghia
1963 VW 1500 Variant Pearlweiss
1969 VW Variant Automatic, Perugruen
1971 VW Squareback Automatic, Clementine Orange
2001 E320 4Matic Wagon- Our belated welcome to the 21st century! Polar White
1973 280SEL 4,5 Sliding Roof "The Bomb", Dunkelblau.

Looks like I will start pulling switches from the yard now.

Now I know why I can't find any Switches when I go to the Junk Yards!

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84 300D, 82 Volvo 244Gl Diesel

Now isn't this odd!

I was looking for information on turbo wine, led to disconnecting the AVR (I.I.R.C. the abbreviation), found a post on here about blocking off the horrific E.G.R., and wanted to send a P.M. to get a block off kit, so joined. If it still has the California crap I plan on getting rid of it. The only useful is the catalyst oxidizer. Now going though posts gaining further knowledge, and find this!

I just purchased this Mercedes 300TDT just before all this happened. Tram has been very kind in all that he has done to have me enjoy a fine German auto that will not need work for a while, and just basic maintenance at that. He never mentioned having this much trouble, and feel sorry for him. Now I know why he mentioned to pull the switches and motors! Dang nabbit, now I am going to have to make a trip to the yard here in Mesa and see if the '85 SD is still there. It was 99 percent complete with the switches last time I was there a month ago. With me luck...

Welcome aboard, Adriel. As to the block off kit, etc. ... this car runs perfectly and always has, so if I were you I'd stop looking for problems and DON'T mess with success. Get the parts but keep them in reserve in case you ever do have issues. When you get the car, even the oil will be fresh; just drive it and enjoy it. That's an order!

Now, onto the window switch issue- this is why I've always bought either new MB or NOS parts whenever possible. These window switches seem to be no longer available at the moment, unfortunately. It's the same old thing we've been running into with our VW Type 3s and "new" aftermarket parts... but at least MB supports their older models FAR better than VW!

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1968 230S Automatic, Elfenbein
1975 O309D Executive Westfalia Camper Bus, Blau/ Weiss
1972 280SEL 4,5 Dunkelrot
1966 VW Type 34 "Grosser" Karmann-Ghia
1963 VW 1500 Variant Pearlweiss
1969 VW Variant Automatic, Perugruen
1971 VW Squareback Automatic, Clementine Orange
2001 E320 4Matic Wagon- Our belated welcome to the 21st century! Polar White
1973 280SEL 4,5 Sliding Roof "The Bomb", Dunkelblau.

Georg, well I will at least run a test to see if disabling the AVR stops the wine. I only found it by accident. The Federals didn't have it, so don't see how it hurt running a few miles.

I am still thinking tomorrow. I plan to have the Mercedes a long time, so just thinking way in the future.

I will just drive and enjoy, when you are done. Still haven't gotten a reply, but don't expect one.

So, do you need replacement switches for the '82? Just want to be sure things are taken care of.

Seems Tram has been too swamped to post up the end, so figure be good to for future referance. It came to replacing some broken wires from the center console to the rear switch. Das ist alles! So, check your wires, then double check again. Hope this helps...