Tailgate window trouble in '91 GW

[jpcoutts]

My new '91 GW is great and for about a month I've been ignoring the fact that the window in the tailgate won't work. Yesterday I decided that I might as well tear into it so I'll be ready when I need to use it. Before I started I read the articles in the tech archives by Michael Baxter ( FSJ Guru) and the others. I got the tailgate apart and determined that the motor works fine by using the direct connection technique suggested in one of articles. BTW, the strips on the floor of the cargo area of your wag make a great ground for electrical connections...near disaster, but that's another story. After tearing the tailgate apart I determined that the PO had disconected the dash switch connector, so I plugged it back into place. Still no response from the dash switch, but by "jiggling" the key in the tailgate switch I could raise and lower the window. Great, I was at least partly back in business. I put everything back together, checked to make sure it still worked with the jiggling technique and went to bed happy that I had conquered the tailgate beast. The next morning the battery in the wag was dead and I then knew why the dash switch had been unplugged. Back to the drawing board. I have a Haynes repair manual and the wiring diagram in it shows the tailgate wiring in the '89 - '91 wags to be different from the earlier years which explains why some of the info in the tech section didn't seem to apply. In the '89 -'91 models there appears to be a relay in the tailgate and the rear switch appears to be grounded separately, unlike the earlier models which have no relay and no separate ground for the rear switch.

Everything is back together, but now nothing is working except the defroster which works even though the plug on the dash switch for the tailgate window is unplugged. Does anybody have any suggestions where to look for the problem?

[LouM]

I believe the defroster uses seperate circuitry which explains why it works. I'm not familiar with your specific wiring and don't have a diagram handy but if it killed the battery, I would guess that one of the switches is sticking and causing the motor to stay on. You might try the back one first since they do seem to be more failure prone and you did mention that you had to "jiggle" the key when operating.

Lou

[RollinTide]

I've got a 91 GW...and an 84 too....double trouble. Did anybody figure out if the 91 has a rear tailgate window relay switch?

[donwag]

My 89GW does not have a relay in the tailgate. I have experienced the battery draining symptom myself. I was the paddle switch in the tailgate getting stuck in the up position when the key was released. Having to "jiggle" the switch to get it work is symptomatic of a sticky switch. The paddle switch is the most probable to fail item in the tailgate window circuit. The dash switch rarely fails. However if you have an open in the tailgate switch the dash switch will not work.

Check the ground up at the dash switch, on my 89 it is the ground for both the dash and the tailgate switches. I have repaired several rear window problems (at least four times) and it has always been the paddle switch failure.

Here is what I did to better engineer my 89GW. By pass the rear switch. Install a remote reciver under the dash and hook two of the channels to the dash switch, one up, one down. Then you have a solid state in your pocket rear window switch. Very handy and works great. I can give you more details if you are interested.

[blackbess89wag]

Hey,

If there's anyway to fix the $%#@*&(^%#) problems with the rear switch, I'd love to know about it. Haven't gotten the rear window to roll down for about 3 months now. The motor is fine, thinking it's the rear window safety switch. Is it easy to bypass?

[jpcoutts]

The rear window articles in the tech section are great. There is even a suggestion on how to by-pass the harness. I tried it and it works. I came to the conclusion that my tailgate switch is bad and I'm waiting until I have the 4 or 5 hours I think I'll need to replace it.

[men in black]

Here's the wiring diagram for a 1990 rear window if that helps!