Rear Window

[Bebop Man]

The tailgate window on my '86 just stopped working the other day. It worked fine the day before, but now it's a no-go.

About a year ago, I replaced the internals (motor, tracks, etc) and ****'d up the gearing.

Checked the fuse panel under the dash, and all the fuses are ok. Neither the dash switch or the key will make it move. There's no indication that there's a power draw on the system at all, hence my thought about the fuses.

I recall someone saying something about wire breaking / corroding. It's been awfully cold here and there's snow, ice, and road slush all over the truck, and I wonder if that might be a contributing effect.

My plan for the weekend is to take the access panel off, and do a volt-check on the motor, but based on everything else, I expect to find that the electrons just aren't getting to the motor. Any good ideas for places to start looking for broken connections?

 

[Bronco_Willis]

If you can test the tailgate switch if you know how to test switches that is. I believe a chilton or haynes explains how to do that. That should tell you if power is getting there.

 

[Bronc76]

The tailgate window on my '86 just stopped working the other day. It worked fine the day before, but now it's a no-go.
About a year ago, I replaced the internals (motor, tracks, etc) and ****'d up the gearing.

Checked the fuse panel under the dash, and all the fuses are ok. Neither the dash switch or the key will make it move. There's no indication that there's a power draw on the system at all, hence my thought about the fuses.

I recall someone saying something about wire breaking / corroding. It's been awfully cold here and there's snow, ice, and road slush all over the truck, and I wonder if that might be a contributing effect.

My plan for the weekend is to take the access panel off, and do a volt-check on the motor, but based on everything else, I expect to find that the electrons just aren't getting to the motor. Any good ideas for places to start looking for broken connections?

If it has a rear window relay, start with that.

 

[Bebop Man]

If you can test the tailgate switch if you know how to test switches that is. I believe a chilton or haynes explains how to do that. That should tell you if power is getting there.

Well, my Chilton's doesn't have anything on testing switches, at least not so I've found so far.

But my understanding is that the dash switch and the key switch are on parallel circuites, so if one malfunctions, the other will still work.

With neither switch working, I'm looking at a blown fuse, bad motor, or a broken connection somewhere.

The fuses test ok, the motor is less than a year old, so i figure I'd start the the high-probability locations for broken connections.

The access panel will be coming off this weekend so I can test the motor, but since I expect that to work, I want to have a Plan B from the get-go.

 

[Croneybones]

Check to see that the tailgate is shut all the way by pushing in on it while trying to use the key. If it doesn't think it's shut, it won't let the window work.

 

[Seabronc]

Well, my Chilton's doesn't have anything on testing switches, at least not so I've found so far.
But my understanding is that the dash switch and the key switch are on parallel circuites, so if one malfunctions, the other will still work.

With neither switch working, I'm looking at a blown fuse, bad motor, or a broken connection somewhere.

The fuses test ok, the motor is less than a year old, so i figure I'd start the the high-probability locations for broken connections.

The access panel will be coming off this weekend so I can test the motor, but since I expect that to work, I want to have a Plan B from the get-go.

Not so about the parallel circuits, close to it but not exactly parallel. They both use the same ground path that must return through the dash switch. With neither switch working it could at any point along the ground return path. Quite often it is the window safety switch, but it could also be at any connection or even a broken wire where the tail gate flexes the cable. Since you didn't say what year truck you have, I am attaching a diagram for 80 - 92 and one for 93 - 96.

Good luck,

>-

 

[Bebop Man]

Not so about the parallel circuits, close to it but not exactly parallel. They both use the same ground path that must return through the dash switch. With neither switch working it could at any point along the ground return path. Quite often it is the window safety switch, but it could also be at any connection or even a broken wire where the tail gate flexes the cable. Since you didn't say what year truck you have, I am attaching a diagram for 80 - 92 and one for 93 - 96.
Good luck,

>-

Thanks for the diagrams. And I thought i put the year in the heading, as well as in the inital post, not to mention my .sig.

Um, which diagram is for the 80-92? Neither appear to be labled.

 

[shift1313]

i did have my dash switch go out once. i had a few jumper wires i would hook up to get the window up and down

 

[Bronco_Willis]

Like I posted before, after I encountered this similar problem, I eliminated my tailgate safety switch all together. So the only way to drop the window is my dash switch. Makes trouble shooting easier

 

[Bebop Man]

Well, I tried pushing on the tailgate, and it didn't help matters. For that matter, the tailgate hasn't been unlatched since the last time the window worked, on Monday.

 

[Bronco_Willis]

use the release latch behind the access panel to drop the window down

 

[Seabronc]

Thanks for the diagrams. And I thought i put the year in the heading, as well as in the inital post, not to mention my .sig.
Um, which diagram is for the 80-92? Neither appear to be labled.

You did, I just missed it :blush: If you look at the diagram, disabling the safety switch doesn't disable the tail gate key switch. A quick check is to distinguish between a bad motor and an electrical problem. Remove the access panel and find the leads to the motor along the bottom of the tail gate. If you can get at the connector take it apart and jumper it to a 12V battery, ( along set of jumpers or an extra battery in the back with you). If you can't get to thew connector, then you can use a couple of strait pins to pierce the wire and do the jumper, (be sure to remove the two fuses, 1 for the driver switch and one for the tail gate key, and be sure to cover the). If nothing happens then reverse the leads (which is what the switch does), If that makes the motor do it's thing then you know you have a connection problem some where along the line. If not, then you know where the culprit is.

I'd like to know where that window release thing is. I have had my tailgate completely disassembled several times and haven't found one yet. Such a thing would have to release the gears and that could hurt if your hand was in the way. I have several tailgate regulators and none of them can be disengaged from the motor.

Good luck,

>-

 

[Bronco_Willis]

Mine is located right behind the access panel directly in the center. I believe the rod extends from the bottom up and you push it down to release everything. I may be wrong, but thats how mine came down. I just used a board about 1 inch below the window so when it came down it landed on the board

 

[Team Knuckleheads]

I had a similar problem on my 1993. I finally narrowed it down to the plug inside of the tailgate. I would move the plug and the window would work fine. So my fiz was to eliminate the plug all together. It is located near the center of the tailgate almost directly below the motor.

Hope that Helps.

 

[Seabronc]

Mine is located right behind the access panel directly in the center. I believe the rod extends from the bottom up and you push it down to release everything. I may be wrong, but thats how mine came down. I just used a board about 1 inch below the window so when it came down it landed on the board

I'll have to take a look at that mechanism again, I could be overlooking something.

>-

 

[Seabronc]

I had a similar problem on my 1993. I finally narrowed it down to the plug inside of the tailgate. I would move the plug and the window would work fine. So my fiz was to eliminate the plug all together. It is located near the center of the tailgate almost directly below the motor.
Hope that Helps.

What year truck do you have?

>-

 

[Bebop Man]

Hey all,

Thanks for the help on this post. Got it all working now.

Turned out that the problem was in the harness plug from the motor to the key-switch.

Combination of corrosion and age led to poor resistance and the plug had actually deformed from the heat. The motor side was all brand new, so i just put in new ends. On the switch side, I ran new leads from the plug to the switch and doped the splices in sealent. Should last for quite a long time.

Thanks again for all your help.

 

[87broncxlt]

i did have my dash switch go out once. i had a few jumper wires i would hook up to get the window up and down

how do you disconnect the saftey on the 87 bronco

 

[Seabronc]

how do you disconnect the saftey on the 87 bronco

It is the same for all 80 - 96. Open the access panel, with the window up you will find it just behind the left tail gate latch. Remove the connector and place a jumper between the contacts and tape it up or cut it off, strip the wires and put a wire nut on it, tuck it back out of the way of the window.

Good luck,

>-