Window motor question (1 Viewer)

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Nov 20, 2016
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Location
Killeen, TX
First allow me to confess my poor knowledge of things electrical, hence my need for advice from Mud members with that sort of expertise.

What would cause a window motor to lower a window, not work when attempting to raise it? Neither the driver’s side switch or the passenger door switch will raise the window, both of them will lower it.
 
Weak motors. When the window glass goes down it has a gravity assist,
when it goes up the motor is working against gravity (the weight of the glass).

The regulator spring does help some as it winds up (gets tighter) on the way down, but with a weak motor (or bad/corroded connections/grounds) it isn't enough to raise the glass, IME

There are other factors, like dry/hardened rubber glass runs and cold weather, but IME the main cause is just an old motor that has lost it's grunt IMO due to weak magnets in the motor case (= less torque developed by the motor) which are not replaceable.

The fix is usually new motors and new rubber glass runs if what you have in there now are original/old. Sometimes once you get into the door you may also find damaged sliders/wheels on the regulator.
 
Weak motors. When the window glass goes down it has a gravity assist,
when it goes up it's working against gravity. The regulator spring does help some as it winds up (gets tighter) on the way down, but with a weak motor (or bad/corroded connections/grounds) it isn't enough to raise the glass, IME

There are other factors, like dry/hardened rubber glass runs and cold weather,
but IME the main cause is just an old motor that has lost it's grunt IMO due to weak magnets (= less torque) which are not replaceable.

The fix is usually new motors and new rubber glass runs if what you have in there now are original/old. Sometimes once you get into the door you may also find damaged sliders/wheels on the regulator.
I pulled the door panel off and tried pushing up on the bottom of the window from inside the door while activating the switch, but it would not budge.
 
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If it doesn't move at all now then likely either a dead motor and/or a stuck or bent/damaged regulator. Only thing to do now is to pull the motor and regulator out and look for something broke. And while it's apart if the motor is the original and even if it seems to be working might as well replace it. If the wheels on the regulator are damaged also time to replace that.
 
Window runs will go a long way to help that. I just finished the driver side front and rear. With this cold weather they would not roll back up. I was shocked at how hard the rubber had gotten. It was more like hard plastic than rubber.
 
Not understanding how the motor and mechanism in the window works is making it hard for me to visualize/conceptualize why it goes down with seeming ease, but won’t even budge, even with me pushing hard on the bottom of the window from inside the door when I try to close the window.
 
Could it be a bad switch? Maybe why you can't get it to move even while pushing up on the mechanism? No power going to the motor in the up position, therefore fighting the whole system?
 
Just had this with a 98 4Runner. Driver window went down with youthful energy, but nothing whatsoever to go up. Master switch was bad - but that's also the window that was bad. Yours is a bit different, given the door's individual switch doesn't work, in addition to the master. I hear you re: thinking it's not just gravity or the window runs. If the motor works, it should power both ways, right? So, maybe the wiring in that door? Not sure. I'm certainly no electrical expert either. It's not impossible that both switches are bad, or that the runs are bad enough + weak motor. Process of elimination 🤷‍♂️

I'm also currently trying to figure out what's wrong with my 80's rear passenger window, and it doesn't make a lot of sense, so I feel ya.
 
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Could it be a bad switch? Maybe why you can't get it to move even while pushing up on the mechanism? No power going to the motor in the up position, therefore fighting the whole system?
It’s weird. I know it could be both switches are bad at the same time, but how often do switches go bad in only one direction?

I’ve watched some videos on changing out the motor and regulators. Seems easy enough. Do people have recommendations on brands to avoid when selecting replacement parts?
 
Here's a great MUD writeup...I may do this when I pull apart for speaker upgrade soon since I very slow rear driver's door window. Not sure if this will be your fix, but could help to visualize some parts....

 
Here's a great MUD writeup...I may do this when I pull apart for speaker upgrade soon since I very slow rear driver's door window. Not sure if this will be your fix, but could help to visualize some parts....

Thank you very much. That was enlightening.
 
I pulled the motor and regulator. Even with no load on it, the motor won’t move the regulator to the raised position. I tried cleaning the contacts. It didn’t help. The regulator and motor actually look really good. Oh well. New ones are on the way. They are due on Thursday so is should be able to install them next weekend.
 
Would be interesting to take the motor apart, some people have found significant corrosion inside the armature case, others have found damaged teeth of the plastic gear.
 
Would be interesting to take the motor apart, some people have found significant corrosion inside the armature case, others have found damaged teeth of the plastic gear.
I’m planning to take it apart and see what I can learn about the motors. If I am able to fix it, I’ll pass it on to someone on the forum in need of one.
 
So I swapped in a new Dorman motor and regulator and it would still only in the down direction. Next I bought new switches. I replaced both the master switch and the one on the passenger door. Now it works fine. I bet there was nothing wrong with the motor and that it was the switches the whole time. Now I have a couple of spare motors and regulators.
 

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