Help! Window has wound itself down and wont go up!

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AlexB
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Currently Drives:: Renaultsport R.S.250 Cup

Re: Help! Window has wound itself down and wont go up!

Postby AlexB » Fri Mar 20, 2009 11:31 pm

The difference is that the stepper motor cannot operate without electronics. It must have at least four wires coming in, but usually more. Brushed motors have just two wires and will spin happily as soon as they are connected to the power source.

I admit, it would be easier and quicker (but not as much fun) to replace the whole thing... Thank you for investigating this issue.

PS: there are a few videos about window regulators on youtube. This is one of them:
https://www.youtube.com/watch?v=_gadOiOarQI
AlexB
(no, a different AlexB)

john10001
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Re: Help! Window has wound itself down and wont go up!

Postby john10001 » Sat Mar 21, 2009 3:08 am

AlexB wrote:At this point I wish I had this part on my lab table...

There are two main options of what may have caused the failure. The first is water ingress/condensation causing corrosion of the PCB tracks. The second is overloading the motor and, possibly, overheating the controller due to glass not moving freely. In any case, the motor is likely to be a more durable part than the controller.

If you feel that nothing more can be done -- break the plastic around the PCB and inspect it. BTW, is it a brushed or a stepper motor? What temperature rating is written on the electrolytic capacitor?


Managed to get the thing half open. Capacitor is rated to 105ºc.

john10001
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Re: Help! Window has wound itself down and wont go up!

Postby john10001 » Sat Mar 21, 2009 3:11 am

AlexB wrote:The difference is that the stepper motor cannot operate without electronics. It must have at least four wires coming in, but usually more. Brushed motors have just two wires and will spin happily as soon as they are connected to the power source.

I admit, it would be easier and quicker (but not as much fun) to replace the whole thing... Thank you for investigating this issue.

PS: there are a few videos about window regulators on youtube. This is one of them:
https://www.youtube.com/watch?v=_gadOiOarQI


I think its probably gonna be stepper motor cause it has 6 pins not just the two.

john10001
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Re: Help! Window has wound itself down and wont go up!

Postby john10001 » Sat Mar 21, 2009 5:40 pm

I tested continuity from one side of the electronic control box to the other and it seems to be okay to me so I guess it has to be the motor. I'm probably gonna buy a new one tomorrow.

John

AlexB
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Joined: Tue Mar 22, 2005 8:17 pm
Currently Drives:: Renaultsport R.S.250 Cup

Re: Help! Window has wound itself down and wont go up!

Postby AlexB » Sat Mar 21, 2009 6:56 pm

Yes, 6 wires represent 3 phases of the stepper motor. It cannot operate without electronics. It's the PCB board inside the connector to blame. I've had the PCB board in the upper stop signal damaged by corrosion. Two printed tracks were repaired by applying conductive paint and the problem was gone. These boards need 3-4 layers of urethane protective coating as they are not hermetically shielded and subjected to corrosive environment (acid rain and winter salt).

I guess, it's the same story with the fuse box, window regulators, hands-free sensors, etc. This saved about a tenner in production costs...
AlexB
(no, a different AlexB)

john10001
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Re: Help! Window has wound itself down and wont go up!

Postby john10001 » Sun Mar 22, 2009 2:34 pm

Thanks! May see if its possible to get a new 6 pin ecu for this window motor before I replace the whole thing. May be cheaper.

I have cracked the whole thing open now. Doesn't look like any corossion but the circuits and tracks are so small I probably wouldn't be able to tell anyway.

john10001
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Re: Help! Window has wound itself down and wont go up!

Postby john10001 » Thu Mar 26, 2009 10:57 pm

Got new motor yesterday and installed. I regreased and the window holders were going up and down the tracks fine. Its strange though because when I have put the window back in, once the window is in, it doesn't continuously go up or down when you hold down the button. It will e.g. just go up for a second to second and a half, about 3 to 4 inches or so then stop. Then I have to take my finger off the button before I press again and it continues going back up another few inches. Its strange how it was working perfectly without the weight of the window in there but going up only a few inches at a time with window back in.

While sorting out this window issue I did also notice that two of the rubber cushions on one of the window holders were missing so I believe that this was the reason I was getting a lot of rattling previously. I sorted that out with an improvised bit of rubber in similar shape and height to the other side. Window does feel pretty solid now and hopefully wont rattle. I also now know why it also met resistance 3/4s of the way down previously because some of the wires were hanging down and blocking in as they hadn't been put back into the rubber stopper in the door hole.

Only issue now is to get the window going up continuously without stopping not in bits and bats.

When I had finished putting the window back in and the horrendous job of getting the door panel back on I did something rather daft. I tried to close the door without having put the electrical connector back in. It snapped one side of the connector lever so I had to superglu gel that back together and leave it drying overnight. Seems to be okay now and connects up.

Will have to test the window and see if I can get it to move continuously with either of the buttons. Maybe try a reset or something. I think for now though as long as it goes up and down and I can close it without it dropping in the middle of the night again then that's fine. Too much hassle to take off the door panel again and troubleshoot.

Thanks,

John

john10001
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Re: Help! Window has wound itself down and wont go up!

Postby john10001 » Fri Mar 27, 2009 10:02 pm

Thanks for you help m8 I will try that tomorrow morning. I just have three buttons on my car, two on drivers side for both sides and one on passenger side just for that side. I dont think my arms can stretch to be able to do the three buttons I have at the same time but can do the two drivers side at once.

Driving home from work tonight and the window didn't rattle once. Not a peep out of it and that's when it usually rattles the most going back up the M621, so I think it was definitely the rubber stoppers on the window holder that was the culprit.

Cheers,
John


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