electric window stopped working

[Kelly]

I have 72 CS with electric windows and the passenger door window has always needed a little help to go up, if it is rolled all the way down. Recently it has stopped working completely and is in the down position. I am not sure where to start my trouble shooting? All other electrics are working, including the rest of the windows. When the button is pushed I can not hear anything. Could it be a fuse, or do I need to remove the button to test it, or remove the door panel and check on the motor? Any help on where to start would be appreciated.
Thanks

 

[Stevehose]

Do you have a plastic access disc in the door panel? If so remove it and feel the motor shaft as you press the switch to see if you have any movement eirther way on the motor. This will tell you if you have a stuck motor - first place to start

 

[MMercury]

I have 72 CS with electric windows and the passenger door window has always needed a little help to go up, if it is rolled all the way down. Recently it has stopped working completely and is in the down position. I am not sure where to start my trouble shooting? All other electrics are working, including the rest of the windows. When the button is pushed I can not hear anything. Could it be a fuse, or do I need to remove the button to test it, or remove the door panel and check on the motor? Any help on where to start would be appreciated.
Thanks

According to your owner's manual - fuse no 9 controls both window motors on the right/passenger side of your car. So while it is possible that a fuse has blown, it is unlikely since you state the rear window continues to function.

Like all electrical issues, you might want to make sure your window motor is getting electricity. You state you do not hear any noise when you attempt to operate the switch. Is there any draw on the electrical system? For example, with the headlights on, do they dim if you operate the switch? If this is the case, the window itself may be jammed. If you can operate the window by turning the gear manually, that is not the issue.

Occasionally, a wire may come loose or have some corrosion which disrupts the electrical flow. By the same token, your switch could have some corrosion or may be worn. You might eliminate the switch as a problem by swapping it with one of the other switches that is known to function. Examining the wiring - will in all likelihood require removing the inner door panel.

There are other possibilities, including a jammed or non-functioning lift motor, but that is one of the last things to check. Having a volt ohm meter or even a simple test light for continuity may not be necessary, but it sure couldn't hurt. Consider reading through the archives on this subject.


http://www.e9-driven.com/Public/Library/BMW-E9-Manual/pages/en/51330050.html#refertoc

 

[Kelly]

Hey thanks for the good info, pages from the shop manual and the quick replies. I just came from the garage and I can detect some current draw when pushing the button and the rear window on that side is also making a noise, but not going down now (it was working a few weeks ago). I do have the disk where I assume a crank handle would have gone. I am going to bed soon, but will check the fuse tomorrow to make sure it is good and to look for corrosion. With both windows now not working I am guessing I have corrosion or a weak connection somewhere which is not providing a good connection and possibly not enough voltage to operate the motors. I will report back after I do a little testing. I do have a voltage meter as well that I can put to use. Thanks again for the helpful post.
Kelly

 

[jmackro]

Most likely your immediate problem is mechanical - not electrical. Stevehose asked the pertinent question in post #2 - when you remove the round plug, and look through the hole while activating the window switch, do you see the shaft trying to turn? If you, do the electricals are OK, but the window offers too much mechanical resistance for the motor to overcome. If you turn the shaft with your finger while pressing on the switch, the window will probably come unstuck. This doesn't fix the problem - just diagnoses it.

Lots has been written here about window maintenance. Disassembling everything, removing hardened grease, re-lubricating, and realigning the tracks works wonders. I added relays to my circuits, and that made a big difference as well. Others have substituted more powerful motors from later model BMW's.

 

[Honolulu]

Stuck windows are not uncommon. What happens is that the window motor is going full tilt and the glass comes to the stop. The motor "overdrives" the window mechanism and it stops in a stressed condition, which the initial torque of the motor is unable to overcome.

If the motor "cliks" when you hit the switch, but no motion, the glass is jammed. Suggest trying to rotate the toothed nylon wheel using the supplied tool or your finger, through the access hole in the door panel.

Also frequently the console switches accumulate crud and need to be removed and cleaned. They can be opened, but at your own risk. Better to shoot some cleaner in the removed switch, wait a while then blow it out with compressed air. Repeat as needed until a VOM tells you the switch is functional.

 

[MMercury]

http://www.e9coupe.com/forum/showthread.php?t=9572

 

[Kelly]

Took the door panel off and got the window unstuck, it is now working. Going to do some cleaning and lubricating before re-assembly. The rubber stop that engages when the window goes down had lost all of the rubber off of it, so I am guessing this allowed the window to go down too far and caused it to jam? Thanks again for the helpful replies.
Kelly

 

[jmackro]

The rubber stop that engages when the window goes down had lost all of the rubber off of it, so I am guessing this allowed the window to go down too far and caused it to jam?

Yup, sounds like a plausible explanation. You might try replacing the rubber tip with a "crutch tip" from the hardware store. Of course, you will need to re-adjust the stop depth to compensate for the thicker/thinner part.

Going to do some cleaning and lubricating before re-assembly.

Removing the old lubricant can be more effective than adding new lubricant. The old stuff turns to concrete after 40 years.

 

[Honolulu]

Let me suggest another replacement for the bump stop. IIRC, the stop is about the diameter of a pencil eraser and 3/8 inch long ... thus, electric eraser "stuff" (says the engineer, who in days past used this sort of thing) comes in a rod of similar diameter, and there are various stiffnesses depending on what you wanted to erase. I'd look for it at a stationer's shop, or drafting supplies company.

The trick will be to adhere this stuff to the adjustable "bolt" that carries the bump stop. Your ingenuity will lead you to a useful and effective solution.