I haven't seen a diagram, but I'll take a look. What's up with it, I've fixed them a couple times.

I went through a few listed in here couldn't find anything with K5 details. http://67-72chevytrucks.com/vboard/showpost.php?p=5621043&postcount=1

 

defroster (actual glass window) or power lift motor? the glass receives (switched) power and ground through the grid. the power motor I haven't looked into.

 

There are 3 wires coming out from a plug in the firewall, I can't remember the colors right now, but they are 3 wires together in a ribbon. Behind the rear bumper under the tailgate 2 of these wires break out into a 2 wire plug. The third wire, I think that it's red or orange, doesn't go to anything and has what looks like part of a glass fuse holder on the end. Someone put a much later model tailgate on and apparently didn't hook things up correctly.

The best that I can tell there are 3 wires coming out of the tailgate. It looks like 2 of the wires are spliced together then those wires and the other single wire go to the 2 wire plug from above.

I know that this probably doesn't make much sense but if I just had a wiring diagram I could figure it out.

By the way, when you try to roll the window down from the inside you can tell that it is putting a very heavy load on the electrical system. The key switch doesn't seem to do anything.

 

It is a heavy load, that's normal. It really draws, or sparks if you jump it.
The plugs are pretty simple and they are special. Mine were rotted and I've never seen replacements.
Going from memory, the two pin connector is positive, up or down, the single is ground.
If the key isn't doing anything, its usually the safety switch. The circuit doesn't complete unless the drivers side latch is closed properly, it completes ground.
I used to sump it with a battery charger, I think I have the polarity right, I've never seen any sort of fuse thing in the wiring.

 

On my suburban gate there are three wires. Two come from the switch on the dash for up /down and the third is constant power to use the key in the gate. I cant remember the colours right now but mine had breaks inside the insulation for the constant. Its a pain where they run above the tank but I managed some heat shrink butt connectors this past winter to hold me over. I had to replace from right before the tank just to where they enter the gate. The two from the switch that go through the firewall I think are blue and red with a stripe or something. I can look in a little bit here. Your constant power isnt hooked up so that's why nothing with the key.

 

That helps, I'm kind of busy today but if I get a chance I'll look at it.

Thanks

 

Also I would 86 that two wire plug. I dont see any need for it unless you're pulling your tailgate off frequently. Just a weak link in my opinion. That third wire should have a plug connector also not a fuse holder. Someone must have robbed that wire for trailer lighting or something.

 

Here's what mine looks like. Orange/black stripe is constant. Blue and the tan with white stripe are for up down. Good luck.

 

Thanks for the pictures. I haven't had time to do anything with it today, don't know if I'll be able to or not.

 

Well I got the time to take the inspection cover off the tailgate today and I found all kinds of problems. The orange/black constant wire is missing about 3 feet. The key switch has only about 6" of the orange/black wire attached and the next place the wire is is behind the bumper. So I think that I have that part figured out. The tan and blue wires don't seam so straight forward. It looks like after the wires come into the tailgate the split and one branch goes to the key switch and the other goes to the window motor. I'm not sure that it's suppose to be that way. Does anybody know if this is right? The motor does work properly from the inside dash switch.

The other problem is that the track on the bottom of the glass is rusted to nothing. I sure hope that I can find the parts that I need to get this fixed.

 

Used or LMC. You won't like the $50/side at LMC :Insane:
Truck Parts and Truck Accessories

Usually, its the Teflon rollers that rot out so the glass jumps the track. Mines all apart so I can't comment on the wiring. IIRC, down was wired to the motor, but up branched off to the DS latch as a safety. I think the key power went through there too, so you couldn't raise the glass unless it was shut.

Your going to make me go look at my spare one buried in the shed sooner or later to look at wiring, arn't you?

 

Well, what can I say.

 

http://www.dieselplace.com/forum/76.../forum/76-speciality-forums/82-exterior/86172-k5-power-rear-window-problem.html

 

Interesting I was thinking there must me a circuit breaker in the wiring which your diagram does show. Im going to rewire my rear window from the firewall back this summer sometime. I'll have to take some pictures to post. Thanks for the diagrams.

 

I think the breaker was inly on the last few years. I don't remember seeing one in the wiring.

I just remembered, my spare tailgate is manual crank.

 

Diaric,

That's just what I needed. I thought that I had looked everywhere, where did you find these diagrams?

 

googled "k5 tailgate wiring", but looked at the images.
Google sucks lately, seem to get better results looking through images.

 

You know, I did that. I guess that nothing jumped off the screen at me.

Now I have to figure out the track.

 

Now I have to figure out the track.

Guess I should have kept parts from the other two I had

how bad is it rusted?

 

It's basically gone on the drivers side. I've had 2 old Blazers here that I got just to pull the 6.2 out of and take the rest to the scrappers thinking that I would never have one. Now I could kick myself for not keeping some more parts from them.

 

I know what you mean. Non rotted tailgates are hard to come by to.

 

I'm just borrowing this thread to post how the tailgate goes back together.
Don't ask why I need this, and if anyone knows where all my pieces are, let me know. :bat:

Like how the spring #23 in image 3 is supposed to be positioned. I have a late 70's one here and the spring is different and wasn't mounted to compare.

 

Oh damn, was that your ziplock bag i threw out last week? Sorry brother. :hehe:

Seriously though....the "spring" in the bottom pic....is that for the key assembly in the TG? Pic is fuzzy & hard to tell.

Maybe i can find a better pic in my FSM for my truck....

 

hmmm, found an image that shows the spring installed as I did. Except it jams the opener.

 

Is that a manual crank TG window?

I can pull the panels off of my '90, but i'm pretty sure i never saw that spring in there a few weeks ago when i put it all back together....

 

Still at a loss on this. The rod pulls up in the mechanism and jams it from turning enough to open the latch's. I'd guess that its supposed to pull down with the latch and help spring it back. Tried the one from my spare gate, but no luck.
You can see from the pic that the rod slides in a notch on the latch like its supposed to, but that jams it up.

While I'm at it. Springs on the side cables. Where are your guys located. The GM schematic in post 23 shows them on the rear corner posts. LMC schematic shows them on the tailgate. My spare gate has them on the gate, wondering if there was different springs for locations.

 

While I'm at it. Springs on the side cables. Where are your guys located. The GM schematic in post 23 shows them on the rear corner posts. LMC schematic shows them on the tailgate. My spare gate has them on the gate, wondering if there was different springs for locations.

Unmolested, this is where my (crusty & broken) cable springs are....

(passenger side)

 

Oh look.....stupid server rotated my pic again.

 

:HiHi:

Thanks, yours is just like how the dealer shows it, with little inserts for the spring to clip into. Different springs than mine, almost seems like the dealer shows it as a Sub cable and LMC has it right for a K5.

This helps, lets me know mine are correct on the tailgate. :thumb:

 

Glad i could help you out.