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My car's driver side power window isn't working. What is wrong and how can I fix it?

The window just stopped working. Everything was fine, then all of a sudden it quit! What could it be and how can I fix it? I checked for a fuse, everything appears ok. Its 1997 Cavalier. I could definitely use some help on this. Its 15°F here and it would be nice to not have to drive with the window down.

It’s either the wndow regulator motor or a frayed or broken wire, most likely in the wiring harness wher it flexes between the door and the body. If you plan to fix it yourself, you’ll need e meter, a diagram of how your door panel is installed, and a wiring schematic. You’ll need to check and see if you have power at the regulator motor when the switch is activated and go from there.


Do you hear any clicking or rattling in the door when you hit the switch? If you do, the window regulator probably broke apart. In that case, it’s recommended to replace the regulator and the motor at the same time.

Are you pretty handy?
If you are, you could remove the door panel and check with a test light if the window motor’s even getting power when you hit the switch. While a wiring diagram would be nice, it might not be strictly necessary in this case, because there should only be a few motors from the switch to the motor.

I checked the fuse, everything looks ok. Do not hear any noises…went down, then it just stopped working. Where do I get the wiring schematic/diagram?

@Ottomotive117 you’re going to waste too much time looking for the wiring diagram. Just take off the door panel and have your test light handy.

Have a close look at the harness that goes into the door. Sometimes the grommet falls out and allows it to rub against bare metal.

Wires rubbing would blow the fuse…Sounds more like the switch or the motor…Either way, step one is to remove the door panel…At least then you can raise the window and prop it up while you chase parts…

I pulled the door panel and checked the wires. I have power going to the plug for the switch, and do not see any wires that appear in bad shape. every once in awhile it makes a noise, then stops…i would guess that means something is trying to work??
…could it be not enough power?

Could be a bad motor. Maybe unburden the motor so it doesn’t need to drive the regulator and see if it wants to turn by itself.

The following idea is based on only a single experience with window motors, but it might be useful. If you’re able to dismantle the motor without a lot of effort, you might take a look at the armature and brushes. On mine, the brushes were badly worn, and the surface of the commutator where the brushes rested was discolored, suggesting to me that perhaps the power was not getting across that contact surface. Here’s a generalized diagram showing a commutator:

What I did was carefully remove the brushes (these are little spring loaded blocks with wires attached, they press on the commutator), and file them flat. Then with some fine emery paper I cleaned up the commutator surface until it was shiny copper. When I put it back together, the motor worked fine, however that lasted only a month or so. Maybe the work I did was a red herring, or maybe the brushes are just worn too far. I’d just buy new brushes if I could find a source, but so far no source for these has appeared, so I’ll probably replace the motor.

At the very least, if you try this and find it solves the problem if only temporarily, you’ve located the problem and know what to replace. You may find that replacing just the motor separate from the lift mechanism (regulator) is a piece of cake, or it may be impossible. If you’re lucky, your auto parts store will sell just the motor, and that will solve your problem. Or you can try a salvage yard if you have one nearby. But there’s a chance you may have to replace the entire assembly even though it’s only the motor that you need.

Since you hadthe panel off anyeay, you could have checked for power at the motor. That would have been the next step. If, with the button pushed, you have power at the motor than it’s either the motor (highly likely) or something in the regulator assembly mechanicals binding the glass.

I replaced my window regulator and motor together from Rock Auto. Part was $75 bucks or so. Worth your time and effort if you are somewhat handy and determine it is the motor.

@gdawgs, I need to replace a window regulator on a friend of mine’s older Mercedes when the weather gets a bit more decent and noticed they had them on Rock Auto.
No doubt you can’t vouch for a specific mercedes replacement part but the part you got was of decent quality, then?

Pardon me for butting in, but…I did find a really poor replacement regulator from a Napa store, and when I got the next replacement from the same store, it was an entirely different design, and a superior one. It was however for a Dodge minivan, so this may not be relevant to your case, but I mention it guessing that the products might be made by the same few Asian manufacturers.

The problem I found was with the attachment for the motor to the door. The replacement resembled the OEM closely- similar looking structure, and three bolts held the motor to the door. These bolts were secured to nuts which were embedded in rubber cylinders that came with the new regulator. That’s where the problem was: these “nuts” looked just like the OEM, but the metal and the rubber were so poorly attached that the nuts simply pulled loose from the rubber. Can’t remember now why I didn’t reuse the old rubber “nuts”, I may have destroyed them in the removal, just can’t recall. I’m assuming that the OEM was made with far more quality than the Asian replacement, that is that the issue was not concept or design, but poor manufacturing.

The next regulator I got from Napa was entirely different - the structure of the hardware on which the motor was mounted was far better, and the attachment to the door was 100% positive, no rubber at all.

My point is to beware if the Mercedes part attaches with anything resembling those funky metal + rubber nuts.

@RemcoW Rock Auto is a very legit website. they have quality parts that I have used multiple times. the window motor i purchased was for a 1998 dodge caravan. it still works today after 7 months of use.

Thanks, guys. I’ll keep both those comments in the back of my head while ordering at some point.

Cav used scissor style window lift. If it is making no noise than I assume motor is failed. 60 online.

The OP didn’t say if he tested for power after the switch.

@Remco@ this is the website I use for my Benz parts

The parts are usually higher quality than the RockAuto parts, but they’re often not the cheapest.


I use this website for my own Benz parts. Higher quality than Rockauto, but pricier.