w124 300CE Window Problems
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300CE
w124 300CE Window Problems
The driver side automatic window is broken. When you roll it all the way up, it does not quit sending the signal and the motor keeps running, causing the window to come out of the track. The same thing happens when you lower the window. If I push the switch to lower the window, it goes all the way down but does not stop once the window is all the way down. The motor keeps trying to move the motor and it makes an awful popping noise. I thought it might be a bad switch, but both switches work on the passenger side window and neither works on the driver side. I took the door card off and all of the teeth are intact on the regulator. I don't think that the motor is bad, because it effectively raises and lowers the window, but I really don't have any idea at this point. Any thoughts?
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300CE
I took the panel off and all of the teeth are still on the regulator. I watched it moving as I moved the window up and down and felt with my hand the ones that I couldn't see and all of them are still in really good shape. I know that it doesn't have automatic up, what I mean is that on the other three windows, when it reaches the top it quits sending the signal and the window quits moving, even if I hold down the button. On the drivers side I have to let go just as it gets to the top or the motor will keep spinning. Then it goes too far and gaps out of the track and it is really noisy. I'm about 98% sure that it is not the teeth on the regulator. I did a lot of research on this before and checked the regulator. The problem that I'm having is not the common one where three or four teeth in a row break off causing the window to not go all the way up or all the way down. My problem is the opposite; it gets to the top or bottom and keeps on going. Whatever it is that is supposed to know when the window is fully opened or fully closed is malfunctioning.
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Joined: Oct 2008
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From: seattle
1990 300ce supercharged and intercooled
There are just stops for adjusting the max positions. The convenience feature module under your rear seat doe the express down function but going up I do not think that it will ever turn off if you hold the button down. But if it does then it would be the convenience feature also.
It still has stops that should keep it from going to far.
It still has stops that should keep it from going to far.
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300CE
I guess I'm not doing a very good job of describing what the problem is. Here is a youtube video showing what is wrong.
http://www.youtube.com/watch?v=-cOoa...4ZU3DHX3BpGrPZ
http://www.youtube.com/watch?v=-cOoa...4ZU3DHX3BpGrPZ
Super Member
Joined: Oct 2008
Posts: 837
Likes: 25
From: seattle
1990 300ce supercharged and intercooled
Ok, so either your regulator or motor or both is stripped out. So when it goes down it will turn off when the amperage gets high enough. Amperage goes up when the window stops turnings. High load. When going up it does not turn current off to the motor when you reach the top. It just loads and binds. If it is stripped either on the regulator or the motor which has a worm gear inside it will do what you are experiencing. So remove the window regulator and if you see no issues with the teeth on the regulator replace the motor.
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300CE
So I think that the problem was that one of the arms on the regulator was bent. I took out the motor and regulator and the motor has all of the teeth on the gear and is strong. There are a couple of teeth on the regulator that are not in perfect condition, but they are in the middle of the cog, not on either end where the problem presents itself. I did notice, however, that one of the arms on the regulator did not look as straight as the other ones. I have ordered a new regulator which should be here tomorrow or Friday. Hoping this fixes the problem....
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88 W124 300CE
MMB I am going to go with Whipple on this one - I don't know what year 300CE you have but I don;t know that there are automatic windows in the 300CE.
Quote from another system >...
"...On mine the Jumping Sound was caused by miss alignment and wear on the irregular wear Regulator Teeth. In my the irregular tooh wear was caused by a bent/warped window Regulator/Motor mounting plate.
You have to pull the the Window Regulator and Motor assembly out to see it clearly. In the pic below you can see one of the areas that was bent. But, take a good look at the Regulator Teeth and you will see they are worn on an angle. The Teeth are supposed to be straight.
Also this is a pic of the one that I fixed. The Driverside Rear was much worse and I replaced it with a new one...."
Have a read of this :
http://www.peachparts.com/shopforum/...air-123-a.html
Quote from another system >...
"...On mine the Jumping Sound was caused by miss alignment and wear on the irregular wear Regulator Teeth. In my the irregular tooh wear was caused by a bent/warped window Regulator/Motor mounting plate.
You have to pull the the Window Regulator and Motor assembly out to see it clearly. In the pic below you can see one of the areas that was bent. But, take a good look at the Regulator Teeth and you will see they are worn on an angle. The Teeth are supposed to be straight.
Also this is a pic of the one that I fixed. The Driverside Rear was much worse and I replaced it with a new one...."
Have a read of this :
http://www.peachparts.com/shopforum/...air-123-a.html
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