99 XJ, 4DR, 4.0, AW4

Recently started having an issue with the driver's side window. One day when I fired up the jeep it just went down on its own and would not respond to come back up via the switch.
What I've done so far:
1. Pulled the door card/panel off.
2. Disconnected/inspected the wiring. Nothing looked burnt visually.
3. The regulator/motor assembly was super hot to the touch
4. It appears (not 100% confirmed)... that only the two wires (for the window control) that go into the plug that connects to the door switch panel are the ones getting hot. And in a hurry when connected.
5. I've been able to fiddle with connecting it long enough to get the window back into the "up/closed" position.

The motor seems to work just fine. So I'm not sure at this point which part needs to be replaced. Is it motor/regulator or is it the door switch/mirror panel that has a short in it.
I don't want to go parts cannon on it. I've disconnected and removed the switch entirely for right now.
Anyone have this issue on theirs?

 

If the window motor is getting super hot then the motor is shorted and needs to be replaced .

 

It got super hot to the touch...and then through the two wires that go into the window switch panel were heating up too.

I was really hoping it would be the switch panel... working inside that door and getting it installed correctly I think will be a monkey scratcher of a deal. I can barely fit my hands inside to touch the motor, let alone replace a part inside there.
Fun times...

 

Also wondering if it's best to replace the whole assembly or just the motor...there's not much difference in price...and then what manufacture is quality for this?.... I don't want to put something that turns out to be a piece of junk and have to do it again...

 

Hold on just a second. A motor gets hot because of current. If it went down on its own and wouldn't respond to the switch commands, it's either a problem with the switch itself or the wiring. XJs are notorious for the wiring in the door panel cracking.

Unplug the motor and turn the key on. See if you're getting voltage at the connector. Now plug in the window switch, key on, motor unplugged. Getting voltage at the motor connector? When you pull up on the switch? Does it go negative (opposite polarity) when you push down on the switch? Does that change when the door is open or closed?

If you need your window back up, you can obviously jump +12v and ground to the motor connector. Change polarity to make it go down. Leave it unplugged if you intend to drive it.

Also, the entire door harness is removable. There's a few connectors under the drivers kick panel, and all the ones on the door. You have to finagle everything through the boot, but it's doable. Once the harness is out, you can see all the breaks in the wires. I can put money on it. There's gonna be some broken wires.

 

I would just go to Rockauto and look at the prices and if you want to get just a motor or the complete part .

 

Dude. It's not the motor. Motors don't just suddenly energize themselves.

 

I would change the complete part because it's a cable drive and it could be bad also .

 

I recently had pushed the boot back to look at the wiring, the only one that was obviously hosed was one of the speaker wires as the PO had upgraded the door speakers. And let's be honest here, Stevie Wonder could've done a better wiring job on it than whoever did it. it was beyond bad. NOTE: That being said... the window issue happened before I pulled the boot back...so I know it wasn't something I disturbed and caused the issue.
Even though the motor/assembly may not be the root cause of this issue.. I may still consider replacing it while I'm in there as it's had 23 years of service already.
I repaired the one poorly done speaker wire. And a visual inspection of what I could see in that segment between door and where it goes into the "frame" of the jeep... all looked good. Nothing looked burnt/melted, etc. Now that was just a visual inspection. I didn't have access to a meter at that time to test the wires themselves.
I've already "jumped" the motor to get the window back up and just unplugged the motor to keep it there. Not sure if it's related but will state this...When the window went down on its own...it seemed to go down significantly quicker than it normally does when I'm operating it with the switch. Are they designed to fail in the open position...say for a safety reason or something?
If it's going to take me removing the harness out of the door like you said.... that presents another problem. If I have to test each of the wires in that part of the harness, right now I don't have time to do all that. Plus my wife wants me to sell the jeep to get a truck....but I refuse b/c I love my XJ...and it was around before she was...so I win b/c her name isn't on the title

 

https://www.harborfreight.com/7-func...g_q=multimeter

If you need help with how to use it, I'd be glad to walk you through that as well

 

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A voltage drop test will reveal a mostly broken wire.

In OP's situation, there shouldn't be power at the window motor when the switch is not being pressed. If there is, a continuity test of the switch can decide whether the switch is at fault, or if it's the wiring. If it's not the switch, and the wires under the boot look good, it's a good chance there are some wires crossed somewhere else.

The multimeter will tell you everything you need to know if you know how to use it.

 

Thanks for the assistance first of all. And when I can get my mitts on a multi-meter I might take you up on that. If it's rebuilding an engine, or any other mechanical part... that's my area of experience.... when it comes to electrical wiring in harnesses, I just haven't messed with it that much. I understand the concepts of all of it... but have only done some basic things.

My initial thought was that the extremely poor patch job the PO did on the wiring for the speaker upgrade (leaving exposed copper even) that somehow current from there would have melted or otherwise compromised other wires in that door harness bundle. But when I looked at it... at least visually nothing appeared burnt or melted on the surrounding wires. But that doesnt mean they didn't touch something up-stream from there that they shouldn't have.
I wouldn't have expected this from the PO...as mine was a 1 owner from new until I got it 5 years ago...and that owner was a city/county gov't.... not some 16 year old trying to create a speaker on wheels. So I was surprised to say the least when I pulled the boot back and saw that pile of garbage.

 

You'd be surprised to know that the people that work on government vehicles will keep them together with chewing gum and chicken wire.