I'd like my car, I hate fixing power windows. I should mention that I don't have a single window working anymore. The passenger front gave up the ghost a few weeks ago. I use the sunroof for ventilation, and I don't want to beat that up and break it as well.

I got into it today, I pulled the cover up, and I saw that both windows on the driver's
side were not plugged into the switches.

So I put the switches in and the driver's window rolled down very nicely. I got about halfway down and thought I better check to see if it'll roll back up. It won't. I think I disconnected it after a similar episode maybe a year ago. I somehow got it back up and didn't want to make that mistake again.

Here is a photo of the jack assembly for the front window, driver side:



I would think one could hotwire it - and if it works fine, it must be the switch. Using my voltmeter, I determined the socket on the upper right is 12V. I got no action either way from jumping that to the other sockets. Maybe there's something I'm missing.

I was thinking, maybe cleaning the switches would be in order. OTOH, I checked the fuses to make sure I didn't accidentally fry one while I was trying my hotwire maneuver - no fuse damage. So maybe it's not the switch. But I took the front switch apart and tried cleaning it. Not sure I did everything right. I'll write that up later.

__________________
Te futueo et caballum tuum

1986 300SDL, 362K
1984 300D, 138K

With the front windows there is luck because at the lower bottom is a junction for the window motor wires. A pic in post 4.

w123 electric window issue

On one door I had the screws get loose and the window motor stopped working.

Unlike your starter motor the grounding the window motor is no part of the circuit. It all goes through those 2 wires. Applying a wire to a positive and a negative on a better gets the motor to go one way and swapping the wires around and the window goes the other way. To do that on the rear you have to locate which of the wires in the switch socket go to the rear motor.

In post 3 is a picture of a window fuse that looked good but when I pulled the fuse the metal nose of the fuse was gone. So, they can look good from the top but are making bad contact on their noses and brackets.

W123 window motor removal

Back to the junction block on the front door. If your remove the motor wires and you have a digital voltmeter you can connect one lead to one terminal and one lead to the other terminal and put it on whatever setting measures 12 volts. From there you can have someone else work the switch and see if the switch works in both directions. On the meter you should see the polarity change.

I don't know how to do that on the rear. I likely would need a wiring diagram or tap into the motor wires to do that.

I had the front passenger side motor totally frozen up. The lubricant had solidified.

Next is the window actuators. The rear ones bend and all have plastic sliders.

__________________
84 300D, 82 Volvo 244Gl Diesel

Oh c'mon, man. Not being able to put your windows down could be a life endangering event. Get them fixed and enjoy your car!

OF COURSE! Clean the modules! If you haven't already, take the door panels off. Yes, I know it's a hassle. Now go do it, and get it done. Watch some YouTube videos of how to do it. If you don't do this, you could easily end up with worse problems later.

Get out all the old grease that has now turned into stiff peanut butter. Replace with new grease. From memory, there's a plastic lift piece in there that has to move well. If it doesn't it will break and you won't be able to put your windows back up. Very bad in the rain I would think.

Get the job done! Do all 4 of them at the same time. Don't doddle with it over the course of 6 months because you'll forget how to do them. Do them all at one time and be done.

Excellent advice here, sorry to act like I was ignoring it. I'll dig into them and see what I can see.

__________________
Te futueo et caballum tuum

1986 300SDL, 362K
1984 300D, 138K

The plastic piece is known as the sliding jaw.

Anybody have an opinion on the best quality aftermarket switches?

__________________
Te futueo et caballum tuum

1986 300SDL, 362K
1984 300D, 138K

No one has ever asked that, and I have seen no response on that. Maybe there is some.

I bought a group of used counsel switches on eBay. Half were real Mercedes switches, and the rest were aftermarket switches. Some of those close to the Mercedes switches in construction but the rest all of the rockers inside of the switch were aluminum and there was only a raised dimple in the aluminum as a contact point on the area. No soldered on like tungsten contact points.

I don't recall any makers name on the switches, and I am not sure where the box with those switches is right now even to post pics for aftermarket switches.

I don't know if I mentioned it in this thread, but I believe when your widow motors have trouble turning be it from the motors themselves and or the regulators the switches have to deal with increased amperage and heat and that is what burns the contact points.

I don't know if one of our members ever took a picture of the insides of the URO switches or not but the URO parts rep comments sometimes in our threads. Perhaps he could take apart one and let us see what is inside of them.

Assuming they work when they are knowing I think you can use the aftermarket switches to trouble shoot by swapping them.

__________________
84 300D, 82 Volvo 244Gl Diesel

Well Pelican parts and another company I used to do business with are selling URO brand switches for around 30 dollars for the counsel switches. I don't know if that is an endorsement.

__________________
84 300D, 82 Volvo 244Gl Diesel

You can get the OEM's, even used ones off ebay will probably work fine.