How about the driver side rear? It is on the same circuit as the Passenger front.

This link may be of some help, although I don't think it provides the answer you are looking for.

Mercedes power window repair - Finninday

It does look like it is most likely the switch that is the problem.

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Graham
85 300D,72 350SL, 98 E320, Outback 2.5

It is for the W123133 (as noted on schematic) This covers several years up to 1985.

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Graham
85 300D,72 350SL, 98 E320, Outback 2.5

The only "133" that I see is the page number.

In any case, I have the 1982 Electrical Troubleshooting Manual; it's not the the same as your schematic. My terminal numbers might not be correct for an '84.

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When cryptography is outlawed, bayl bhgynjf jvyy unir cevinpl.

I admit is not clear just what that 133 means. I see in the later ETM that the power windows schematics are on pages 132 and 133, so you could be right.

Regardless, it seems I do have the later schematic too. If the switches have internal LED backlighting, then this schematic should be correct (it is for my 85)

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Graham
85 300D,72 350SL, 98 E320, Outback 2.5

It's the page number. No doubt about it.

__________________
When cryptography is outlawed, bayl bhgynjf jvyy unir cevinpl.

Your readings are not unusual. These motors run on current through an inductive motor. The voltage will "appear" to drop to zero as the only resistance is the windings. The only true way to determine a problem is with an amp meter connected in series.

Both power and ground are switched...... through the switch itself. This is how the motor changes directions.

Most of the window switch problems I've had are dirty contacts (probably due to their location). Pulling and soaking in a cleaner, such as electrical contact cleaner, then drying them thoroughly has always resolved the problem.

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Sam

84 300SD 350K+ miles ( Blue Belle )

Only one terminal is switched (from power to ground) per switch actuation. The remaining terminal is not switched unless the switch is actuated in the opposite direction. (In which case the originally switched terminal isn't.)

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When cryptography is outlawed, bayl bhgynjf jvyy unir cevinpl.

It's hard to explain. At rest, both sides of the motor are powered. Direction selects which side is removed from power and ground is applied to.


OOPs! please note reason for editing!

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Sam

84 300SD 350K+ miles ( Blue Belle )

Evidently, my schematic-reading abilities are not what I thought they were. Same for a volt meter.

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When cryptography is outlawed, bayl bhgynjf jvyy unir cevinpl.

No, you're reading fine.

Both terminals are powered 12V+ at rest. The motor doesn't run because potential is the same at both leads. When you press a button, one side or the other is switched to ground. Ground is supplied through the brown wire on the driver's switch, not locally in the door.

You don't need to measure current: since your motor works when powered directly, not a short circuit.

If you have power at both leads at rest, and you're sure there is no power on both leads when you press a button, the only explanation that makes sense is a bad switch. What you may want to do is measure RESISTANCE between each of these terminals and ground when you press a button. That would determine is whether they are simply disconnected, or switched to ground.

The left and right switches are NOT interchangeable, that's not a test. You need to buy or borrow a good left side switch and try with that.

OK, this was where I was heading...I was stuck on the fact that the drivers side switch - when installed on the passenger side - also did NOT operate the motor. But, if the switches are NOT interchangeable, then that could explain my problem (and I was wondering about the interchangeability due to the middle button connection on the driver's side switch that locks out the rear windows).

ryan

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RG Newell

1984 300D
1972 250
1986 560SL
1991 300CE

That's why I recommended that you jumper the connector terminals. But the terminal numbers that I provided might not be right for an '84. The basic idea can be garnished from the provided schematic, even if the terminal numbers and wire colors are different.

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When cryptography is outlawed, bayl bhgynjf jvyy unir cevinpl.

When I took My Counsel Window Switches apart they were beyond any sort of chemical cleaner. I used a small Pocket Knife Blade to scrape the burned/oxidized part off of the Contact Points.

Also keep Brake Cleaner away from the Switch as it softens the Plastic.

In the picture the contact that is circled has not been scraped. The 2 lower ones have been scraped but notice the craters on them.

There is other Contacts on 2 the Rockers that are not shown in the Picture and there is other parts not shown in the Picture.

Attached Thumbnails

 

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84 300D, 82 Volvo 244Gl Diesel

On my '85 300d:

- rear windows worked until recently from either center console or door switches. Few months ago I noticed left rear worked when it felt like, from either switch.

- now neither side works from the door switches.

- right side works from console, left does not.

- left side: getting power to socket #7 with key on.
- right side: getting power to sockets 3 and 7, key on.

- have tried three switches on left door window motor, both spade connectors on the motor stay hot all the time regardless of switch position. I have one of the soldered-on-connectors motors.

UPDATE: turns out my multimeter has issues. Borrowed one, looks like I have no ground at the brown wire socket on the left door.

Does the ground go through the switch on the console? (I am Forrest Gump on electrics.)

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Mac
2002 e320 4matic estate│1985 300d│1980 300td
Previous: 1979 & 1982 & 1983 300sd │ 1982 240d

“Let's take a drive into the middle of nowhere with a packet of Marlboro lights and talk about our lives.” ― Joseph Heller, Catch-22

The chassis ground wire connects to pin 4 of both console switches. There is a ground conductor within the switch that connects to pin 4. Internally, there is a connection from this internal conductor to the safety switch and from there to pin 5. It is hard to describe in words, but You can see this in the diagram I posted for the 85. If the safety switch is open, then there is no ground for the rear motor and the rear window cannot be opened.

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Graham
85 300D,72 350SL, 98 E320, Outback 2.5