Elec. window/ lock harness question

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DanMcG

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Headed out tomorrow to look at a pair of electric window doors, and was wondering how much of a battle it is to pull the harness out? and any tips that would help it the process?
Basically is it right there, or is it buried behind everything?
 

yevgenievich

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It is a bit burried and most of the dash needs to come apart. The hvac box can stay in place. Maybe can pull it out with just removing the cluster and glove box
 

Snoots

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Ditto.
Take a razor blade to cut the harness tape. Get every inch of the harness you can. You should be able to get it all the way to the fuse box without too much trouble . . . if you're a pretzel.
 

hatzie

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It's an optional setup. The ones I've pulled were not super seriously integrated with the main cab harness. GM didn't make every truck with electric doors, AC, or NL2 dual tanks so they are sub harnesses that could be added when the line saw the RPO codes on the build sheet. Heat without AC is actually a sub harness that plugs into the HVAC power wire under the dash.

You will have to pull the glovebox and instrument cluster at the very least. Access to the fuse panel is a must. It's plugged into the fuse panel using Pak Con connectors that are made of unobtainium so don't just clip off the wire. The ground for most of these optional systems is plugged in just above the E-Brake... or screwed down with a ring terminal.

Make sure to bring a drill to de-cap the door wiring bellows rivets so you can liberate the wiring bellows that run between the doors and the body. You need those bellows. Hopefully, the present owner didn't take the clippers to them... I don't think they're repopped. Split loom will protect the wires but it will bring water into the inside of the cab. If you need em you can probably liberate some off many later model cars and trucks and retrofit em.
 

T-ROD

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If your planning on keeping it exactly like factory it may be a a real PITA, but on the other hand there is on most of our trucks, plenty of outputs open on fuse box for options, you'd need about a 20 Amp circuit breaker, in place of the fuse , and it could be nicely wired into fuse panel with little effort, just that you'd probably need to find a way to put boot from door into the body and it should come out right behind the plastic kick panel if you got them at the very top under the dash, then you could run the wiring to the other side, and Ground it by ring terminal somewhere good to an existing screw on interior or firewall and main thing is power too just hook it up to the ignition fused outlet where one may be in the fuse box
 

chengny

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The devil is in the details on this one.

When I did this modification for the first time - like Travis says - it was an absolute pain in the ass. And that was only because; I wanted to maintain the integrity of the OEM wiring (i.e. did not want to cut and splice the original wiring/switches/connectors). In order to do that, the harness sections that run to the doors have to be disconnected from the middle section that runs from left to right under the dash:

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and then, entire wiring group to each door has to be pulled out from the cab - through the openings in the body, through the rubber boots, through the openings in the door and finally out of the door cavity. It is not possible to pull the wires into the cab due to the dimensions of the switch sets.

I was doing this in a junkyard, by myself and it was my first time. Since the harness was for both PW's & PL's ...the wiring bundles to each door were as big as they get. (And because of the two master switches in the drivers door, the section of the harness that goes to that side is basically double the size of what goes to the RH door)

When I tried pulling the harness out of the cab and into the door cavity, the connector ends kept hanging up in the rubber boot, so that needed to be released by hack-sawing through the flange rivets. Of course at reassembly, the flanges had to be re-riveted.


But I finally got both of the side sections out. Then, at some point, it was time to fish the harnesses back through everything and into my cab. Fugget about it!

If I thought pulling the harnesses out was an ordeal - pushing them back into the cab made pulling them look like a day at the friggin' beach!

I learned my lesson. Now when I pull those harnesses, the first thing that happens is the door is released from the hinges, the rivets for the conduit flanges are drilled out and the door is hung from a chainfall. Only then do I start to pull wires.

There are 3 holes in the wheelhouse inner wall.

The top one is for the roof marker lighting harness and the middle one is for the PW/PL lock harness:


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The lowest one is for the door jamb switch (dome light and "key in ignition" alarm):

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The A pillar and leading edge of the door are pre-dimpled at the factory to show the proper location of the conduit flanges:

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Note that the hole for the PW/PL harness is above the top of the upper hinge - and the conduit opening will be drilled about halfway between the hinges. So the harness must go through the conduit and pillar opening - then up to the hole in the inner wheelhouse wall. Then it takes a turn inward towards the cab.

I don't mean to discourage you, but the process will require some degree of patience. And in the end you will be riding like a rockstar.
 

DanMcG

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Thanks for the insite Jerry, We'll see what happens.
 

Snoots

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chengny, You ROCK!

That's a great explanation with pix.
There was another member who recently added this to his truck (a beautiful gray one). It's on this site somewhere. That will offer some help too.
 

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Someone posted up the diagram for adding relays for the windows so all the power doesn’t go Thru the old switches

I would add the relay in while you’re doing the swap
 

SDJunkMan

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This is good timing for me, the parts truck I bought a while back has power windows and locks that I am planning to put on one of my squares. I was wondering how much trouble it was going to be to take the harness out.
 

gmachinz

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Or for those who have butchered wiring....here ya go! I’ve got a decent stock of NOS relays for people who are doing a full on conversion and need the entire harness run and relay. This harness is stock OEM style but I have them with relay and auto down/up options also!

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DanMcG

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I Thought I'd conclude this thread with what I learned. I originally went to get some nice doors, door panels and the electric window harness..... Well after ten minutes of talking trucks, the seller tells me. " my 5 yo son wants me to keep the truck, he said it's his, I can't sell it." I was a little ticked, but how can you argue with a five year old.

Anyway, I came across a guy parting out an 80 c10 in nice shape I was to late for the doors and fenders, but got a nice hood and the electric window harness.
The harness was a piece of cake getting out only because the dash pad and instrument cluster was already out. I don't think it would be possible any other way, It runs at the very top of the dash over the top of everything. the drivers side was the toughest getting out, you have to fish it up through all the other wires and whatnots. I had to cut the ground and pull the hot wire out of the fuse box. after that it was simple.
All in all it was probably a 15 minute job.

That's all I got for ya, the old guy (82) was a hoot, I think he had the energy of a 30 year old. He sold me the hood for 50, the harness for 15 and door panel with the carpet bottom panels for 30. I was happy. Now all I need are regulators and motors.
Thanks for all the advice everyone.
 

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