I have a 79 300D and just the other day I was running errands and had the windows rolled down and then after one stop I get into my car and try to roll the front passenger window down and it won't budge. I took the door panel off and when I push the switch, you can hear and feel a clicking that is right before the motor, but the motor is not turning as I took the cover off to look at it. I called my mechanic today and he said it most likely isn't the motor, might be the regulator jambed up and said he'd just have to look at it, but I don't have time to take it into the shop since I need the car everyday. Tell me how to test the regulator and get the stuff out of the door without the window crashing down. The window is rolled up as mentioned before. I just want to get this fixed ASAP b/c w/ no automatic passenger window it sucks to roll down just my side.

There are plenty of descriptions in this Forum about how to remove the door panel and check this. I had a similar problem, but my window motor was shot. Prices for these vary A LOT. I think I paid under $80 locally for a new Bosch motor. I had to solder the connection wire, but it wasn't as hard as I expected.

Good luck!

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Semibodacious Transmogrifications a Specialty

1990 300D 2.5 Turbo sedan 171K (Rudolf)
1985 300D Turbo TD Wagon 219K (Remuda)

"Time flies like and arrow, yet fruit flies like a banana"
---Marx (Groucho)

I think you misread my post, I already have the panel off, I just don't know how to check to find out whether it is the motor or regulator that is bad? Also how to get them out w/out the window crashing down

Ganimal.. do an inspection of the regulator first. Check to see if there is any cracks or defects. Check to see if the teeth on the regulator are worn or not. Check also where the plastic tabs, they are white in color... and these are the parts that connect the regulator to the window. If these are OK.. check the motor next. I would simply check by hearing sounds if its running. There is probably an electric tool/device that does this, but don't know the name.

DUCT TAPE!

Sorry I didn't understand. Maybe this will help.

Take about two one foot lengths of duct tape (or perhaps duck tape) and lay each piece over the top of the door so it hangs down evenly on each side, and then stick it firmly to the glass on both sides. I think one piece would do it, but you could use more or longer pieces for greater security. I imagine that package tape (the plastic kind) or masking tape or plastic electrical tape would also work.


The goo that might stay stuck to your windows can be removed with rubbing alcohol (the cheap, clear kind).

You can test whether current is getting to the motor with a test light or buzzer. Clip the gatorclip to ground (any bare metal inside the door, and place the pointy end on each connection) Turn on the ignition, then press the button. If the light comes on, then you know that current is getting through The connection you were touching is the hot wire. Usually the ground wire is black on Mercedes.

The motor is held on by three nuts. You will have to feel around on the backside of the motor for at least one of them. Check each place where the regulator mechanism has a joint to see that there is not something twisted or jamming. Check the bottom of the door for bits of broken plastic.

You may not need to replace the motor. The motor may simply be restricted from moving by a bent joint in the mechanism.

When you have replaced everything that is not working, spray some WD-40 on all the connections and replenish grease to anything that seems to have had grease on it.

There are four places where a power window can fail: the switch, the motor, the regulator assembly and the wiring.

Also the first place to look: the fuse, of course.

Good luck!

If the regulator assembly is shot, and usually it just needs new plastic sliders, your best place to get a new one is a junkyard. The assembly is different for each window LF,RF,LR, RR: so are the motors, at least this seems to be true of my car.

The check strap on the door can also keep the window from rolling down all the way on some models.

__________________
Semibodacious Transmogrifications a Specialty

1990 300D 2.5 Turbo sedan 171K (Rudolf)
1985 300D Turbo TD Wagon 219K (Remuda)

"Time flies like and arrow, yet fruit flies like a banana"
---Marx (Groucho)

Thanks for that info, but how do I get the window hardware to come down so I can take the regulator out, I'm not sure which screws to undue on the metal in order to get the mechanism to fold down so I can work with it. Do I still need to use duck tape for the window doing this? I got another manual today and it said to get the window down to work on the stuff, how do I get the window down if it is stuck up? Thanks

My car needed a new lifter motor and I kept the window up the entire time.

If you need to lower the window, I suppose you unbolt what you can with it up, then untape it and perhaps have someone else gradually lower it.

There are bolts you can feel, but not see, facing the outward side. The window motor is soldered on, or at least mine was. To completely remove it, you will need to melt the solder. The motor raises and lowers the glass, so if you remove it, you should be able to position the glass whereever you wish for best access.

However, you can probably unbolt it entirely and the window can be put down.

Look for broken plastic fittings. I think somewhere in this forum it says that these often disintegrate with time.

Mercedes sells a repair kit for about $5.00.

Good luck. I hope this helps.

__________________
Semibodacious Transmogrifications a Specialty

1990 300D 2.5 Turbo sedan 171K (Rudolf)
1985 300D Turbo TD Wagon 219K (Remuda)

"Time flies like and arrow, yet fruit flies like a banana"
---Marx (Groucho)

Thanks, but what exactly do you think I should do to figure this problem out? My mechanic said it's most likely the regulator, so should I just unbolt all I can and lower it to look at it or what? I just don't want to screw this stuff up haha, try'n to fix it.

There has to be a point in time when you will need to take the car in for a day. Will your life end? Ask your mechanic to order both parts so he can fix the problem in a day or less and send the uneeded part back. If you depend on that car so much, you are going to be in real trouble when a water pump or something goes out. I think you need to start planning.

Peter

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Auto Zentral Ltd.

You could take a bunch of digital pictures of it before you dissassemble it.

If you don't have a digital camera, you can draw a sketch of what goes where, and write down which pieces connect at what an angle.

Look for those plastic parts and for broken bits of plastic in the bottom of the door. If you find broken plastic, that's a regulator problem. Replace those parts, taking as few pieces apart as you can.

If the motor is binding, it will be binding at some particular joint. You might turn on the ignition and fiddle a bit with the window switch and check to see what it it trying to move.

Remember Right is tight and left is loose.
Righty-Tighty, Lefty Loosey

And good luck.

__________________
Semibodacious Transmogrifications a Specialty

1990 300D 2.5 Turbo sedan 171K (Rudolf)
1985 300D Turbo TD Wagon 219K (Remuda)

"Time flies like and arrow, yet fruit flies like a banana"
---Marx (Groucho)

Man this has become a pain in the ass haha! Well I have no idea how to get the motor out even when I unscrew the nuts along w/ the screw that is in the back of the motor. Well today I was doing some other maintenance to my car and I decided to mess w/ all the switches to see if the rear window that is working would make the front window work, well it didn't and I got to where I switched all the ones that did work to other switches but would only work on the one that they came from, what the crap is up with this? Is each switch different or something? Also the I can't get the switch for the broken window to click anymore, I dunno what is going on here.

Sorry this is giving you so much trouble.

I had no difficulty removing the motor. I suspect that this was easy for me because I had a new motor to look at and could see where all the conections were, but if you unbolt all of them (there are three or four bolts at most), it is quite easy to remove, other than unsoldering the electrical connector. All I did was pry it out a bit and twist it gently.

As I recall, when I hit the switch and the window did not come down, it make the courtesy (interior) light dim a bit. That is how I knew it was not the switch. If it had been the switch, there would have been no electrical resistence and no dimming.

My switches seem to be interchangeable, if you line up the hot wire and the ground in the proper positions. I seem to think that some plugged in backwards. But there may be a difference between my 85 and your 79. I know the door lock vaccuum pods are different.

When I went to put the motor back in, I recall that holding the bolt or nut (I forget which) in position with a magnet proved helpful.

__________________
Semibodacious Transmogrifications a Specialty

1990 300D 2.5 Turbo sedan 171K (Rudolf)
1985 300D Turbo TD Wagon 219K (Remuda)

"Time flies like and arrow, yet fruit flies like a banana"
---Marx (Groucho)

I think I'm just gonna take it in next week, I already have the panel and everything off, just need the part replaced if it's the motor so shouldnt' be too bad