1990 Rear Power Window - WTF?

[Badwolf]

I've been having all kinds of problems with the rear window - not going up or down. Luckily, for now, it's in the closed position. I'd like to be able to get the thing to work by the time the warm weather shows up.

Last weekend, we took all switches and connectors (both the console and in the rear door) apart and cleaned them and re-connected them. The window worked (prior to buttoning everything back up. Figuring we fixed the problem, we closed everything back up and low and behold -

IT DOESN'T WORK!

What the hell am I missing here?

Is there a relay somewhere that I need to check?

Thanks for any and all pointers here.

 

[MarzipanMcPig]

not sure what to tell you as for why it is broken right now, but i know on my '95 [it may be all 2nd gens, or maybe only certain years] there was a recall on the rear window crank or whatever. when i bought mine half a year ago, the guy replaced this part on it for me, as the old one had this problem. thing is, i'm pretty sure he replaced it with another of the same thing from a junkyard, and it seems to be slowing down again. i try not to use it if i can, but i'd like to eventually replace the crank or whatever it is that keeps breaking.. so if anyone has advice for you i'll be keeping an eye on it as well lol

 

[tonystewart02]

I didn't see anything in your post about it so... In my '95 (and I'm assuming yours is the same), just behind the storage bin in the driver's rear quarter panel (behind the trim) is the rear power window and wiper control relay. It provides the interlocks and warning signal for the rear window and door. A copy of the FSM (pages 122-126 of the wiring diagram section in the '95 FSM) and a multitester should get you headed in the right direction.

 

[run4yota]

not sure if this is your problem, but i had the same thing happen to me, i took the motor apart and cleaned the brushes, and contact points with fine grit sand paper (which did help it move up and down faster) and i could manually make it roll up and down by jumping the wires out, but when i plugged in all the safety switches i had a no go. weeks later i realized that my rear wiper was not all he way up. i took the wiper off and turned the wiper switch on and off once to reset it and now the window works.. simple fix to a big headache.

also i heard that there is some way to reset the window control board, i forgot how to do it tho, i'd say it's worth googling.

 

[foonanas]

not sure if it applies to 2nd gen. but on a few first gens I worked on the tailgate wire harness had wires exposed. My harness comes near the rear tail light and comes out under the body and then goes into the tailgate. I would check that area as well.

 

[Bad_Vision]

I've been having all kinds of problems with the rear window - not going up or down. Luckily, for now, it's in the closed position. I'd like to be able to get the thing to work by the time the warm weather shows up.

Last weekend, we took all switches and connectors (both the console and in the rear door) apart and cleaned them and re-connected them. The window worked (prior to buttoning everything back up. Figuring we fixed the problem, we closed everything back up and low and behold -

IT DOESN'T WORK!

What the hell am I missing here?

Is there a relay somewhere that I need to check?

Thanks for any and all pointers here.

Ok you monkey around with the wires in the tailgate and it works so you know your issue is in the tailgate
when you tug on wires and it works it sounds to me like a grounding issue, i know on the 1st gens the drivers side tailgate latch has a switch that wont allow the window to go up and down unless the latch is locked in (as if it was closed)
Now one thing to look at is the tailgate grounds them self witch means were it bolts on to the body, i live in Michigan and this is the number one cause rust can build up between the bolt on plate that attaches the tailgate to the body take the tailgate off and clean the contact point with some scotch bright pads. this will ensure a good ground to the body.

Now as with all the other ground points its a good idea to take them off and make sure it hits bare metal then check and see if the tailgate works a bunch of times if this solves the issue then you cover the exposed metal with a clear epoxy to seal out moisture

If good grounds dont make the difference then you need to take a voltmeter to every wire in the tailgate harness and get your FSM out to make sure they are all getting the right power, if one has less then what its supposed to i would trace the wire to its source and look for exposed copper that would (leak) the power or even a broken section that may have been tugged by the tailgate.

 

[Badwolf]

So on Saturday, I got the window down again, and decided to find the damn relay/power window controller/solid state module - what have you. I disconnected it, shot the connection points, unattached the module from the bracing member, and opened up the module. It's all solid state, but it was very clean. I didn't see anything burned out, leaking, etc.

The problem is that without pretty good electronic diagnostic skill, you're not going to be able to figure out if this is the weak link. I reassembled everything, and The window is still sketchy, but can be raised and lowered if absolutely necessary.

Next step - check the tailgate grounds. Thanks for the tip.