GeorgeK

Here what I have:
-Driver side window gets iteratively stuck closed, with no rime or reason.
-Always have current, there is draw when I use the switch.
-When stuck, I remove the tweeter, get through the door membrane and turn the motor axle one tiny bit (it is hollow and takes a 4mm allen). No force needed, no "unblocking" feeling. Works again, for an unknown amount of cycles, until it gets stuck closed again.

What I have done:
-Changed motors, I am on the 3rd, all good motors.
-changed the whole scissors for one from a low-miles car
-Changed the window guide felts, the old ones were very worn, a bit sticky. Put new ones in.
-Changed window holding rail, old one was badly rusted.
-Checked wiring, all is fine, and I do get draw when the window is stuck.
-Played switcharoo with the switches, no change.

At this stage, I am considering converting to manual windows. Last time I unstuck it, got stuck again the very first try. Of course with the AC crapped out, it gets old quite quickly now that the weather is finally warm.

Any help, potion, voodoo, curse welcome by now.

Rocket Rob

Sounds like a frustrating situation. What is your battery voltage with the engine off and on? Could you have a low voltage situation? What is the voltage at the motor? And how clean are your grounds?

beetle08

Did you purchase new motors or used motors?

GeorgeK

Voltage I have not measured, but the passenger side window never gets blocked, so I guess it is not the issue.
Motors were all used, althouhgh the last one is really fresh looking.

Rocket Rob

I would measure the voltage. It may confirm that you are getting good power to the motor, hence the motor itself is faulty or weak or if the voltage is low then you have a wiring or ground problem upstream.

GeorgeK

Good idea. i will do that this weekend and report.

neanicu

Disconnect motor. Use jumper wires from a 12V electric tool battery or the car's battery. Supply to window motor. It should run in one direction and if you reverse polarity,it will run in the other direction. Make sure you do not touch the jumper wires together. If motor works each time,your problem is not the motor,but high current draw between the switch and motor. Check wires and window switch. If everything ok,you'll need a wiring diagram to see from where are the power and ground coming into the switch.

dhc905

I posted a DIY on repairing/replacing the motors/window items. I would maybe check the gears on both the motor and the scissors; I'm pretty sure that if they get misaligned the motor will automatically shut off rather than burn itself out. The fact that you reach in and "tweak it" with the allen wrench and it starts working again leads me to suspect something of that nature.

Also how are those CREE bulbs working out for you? Swiss post finally deliver?

GeorgeK

Nicu, I will look into that. My issue with an electrical fault is that the fault appears with no defined cause. There is no relation to load, as sometimes I can cycle the motor 20 cycles with no problem, and sometimes it gets stuck within 2 tries. A bad contact would be considered, except that when it is stuck and I toggle teh switch, there is a definite load, which means the motor gets juice and tries to pull.

As for the misalignment (dhc), same remark; why does it get stuch haphazardly? and with now the 3rd scissor, 3rd motor?

Anyway, I will take the door apart (takes lass than 10 minutes now, I have exercise...) and break out the multimeter.

Thank you for the ideas.

DHC, topic on the CREE bulbs coming up, with pics the way I wanted them forever, and a test through an aiming machine.

dhc905

Cool. Looking forward to the last word on those bulbs.

Couldn't explain why they were getting misaligned; are you sure you've put all the bolts and leverage points where they're supposed to go? I could see if you're missing a bolt how torquing it on the up down could jack the alignment out...

dhc905

FYI: See my thread, I have a good graphic of all the connection points.

https://rennlist.com/forums/964-foru...regulator.html

StopLookGo

Mine had a similar issue. Turned out to be the worm gear I think according to my mechanic. Swapped it out with one from a wrecked E30 BMW and has been flawless since.

GeorgeK

Took the door apart, got the multimeter out.

As luck has it, the motor was stuck when I took it apart. First time it is stuck in the doc's office.

See pics with text.
At the end, it took less than 5° rotation of the allen key, and it got unstuck, only to get stuck again haphazardly. At this point, I am thinking that the gears get stuck, maybe combined with a weak motor (although is seems to come from a low mileage car..?)

Spyerx

I had a similar problem to this on my 89. I ended up opening the motor and greasing the worm gears and motor bushings internal to the gearbox and greasing the window gear components. It's working fine now. Key would be checking amp draw when it's working compared to other window for me it was much higher showing drag that would sometimes stick the motor.

GeorgeK

I did exactly that. Took the motor apart checked the contacts that are very good, greased the gear and axle, put it back in. Closed the window, and went to care for other stuff.....

Came back 3 hours later to a stuck window!

So I took another motor I have, greased it, and put it in.

Then I noticed a thing: the travel limiter of the scissor might be involved. I noticed the window does not close with such a good "thump" at the top as the passenger glass. So I moved the limiter a bit. and cycled the window a few times. Now it works. For how long??

One thing is sure, that door is not going back together for a few weeks. I'll daily drive the car as before and we'll see what happens.