What's new
CK5
Register an account today to become a member! Once signed in, you'll be able to participate on this site by adding your own topics and posts, as well as connect with other members.

Ok I am losing my mind on this interior lighting

Think this would cause issues? I pulled the dash and cluster to inspect and probe and this loom went up just under the VIN number. Found a few inches of exposed orange wire. It looks like it this group of wires was one unit and it has a black and white and 2 orange wires.

20200905_094539.jpg
 
Holy crap the previous owner did a nice job hiding all of this. The wiring going to the horn relay was completely melted. The horn didn't work when I bought it and now I know why. I put a new relay and it was working.

20200905_101807.jpg
 
I went down the rabbit hole looking for the rest of that wire. I found it unfortunately. It goes to the back of the fuse box and it's melted there too. I don't know how to get that brass contact strip out to try to repair it. I guess my only option is to buy a new fuse box/wiring harness and that's probably a good idea at this point.

20200905_114031.jpg
 
I think the replacing of those contacts has been done here many times before. I suspect someone will jump in and tell how. If that wire is after a fuse, the PO did something creative with the fuses. Preventing stuff like that from happening is kinda why you have them in the first place.
Obviously that wire was shorted somewhere, and after the insulation burned off, the bare wire could make contact with all kinds of things.
Both a ground, or a hot terminal. Since a large part of your problem was something feeding power when it shouldn't, that wire touching a hot might be what caused the problem.
Also, notice on Wes's list, the horn fuse is the same as the lighter fuse. So, if that wire is shorted, its a good candidate for the lighter problem.
 
Yeah I'm 100% convinced this was the problem. That harness that was chaffed was tucked up against the body sheet metal basically touching the bottom side of the sheet metal that the VIN is riveted to. I pulled it down and noticed the bare wire then traced it all the down to the fuse box. The other lead from the horn relay comes out of the relay and goes to the harness for the under dash courtesy light and it's melted as well.

If I could repair this harness and that fuse box situation, I would love to. I even thought about puling it all out and taking it to the a repair shop around here if there is one. If not, I know a guy on Facebook sells the fuse box and a whole new wiring harness for under the dash for around $340 which isn't bad for all new wiring etc.

There are a few other places that this harness was hacked one from an alarm install many years ago but I pretty much fixed all of that.
 
Those color wires (orange & white) are the ones that go to the dome light and courtesy lamps on my square body,I'd say you found the problem..I think the orange is "always hot power" and the white wires ground thru the door switches,I could be wrong though..

When I scrapped a '73 K10 I kept most of the wiring harness,in case any of my other trucks ended up like yours..but year to year they did change some things,so its a "maybe" if it'd work on an '80's model truck..wish now I had kept a lot more wiring off other trucks I parted out,its getting hard to score any at salvage yards,they are all hacked or the trucks were burnt..
 
Yeah that wire that is melted was constant hot. There are only 2 junk yards withing 30 miles of me that have a single square in them and they are heavily picked over. I might go see if the one by my house has the fuse box in it and just cut it out and buy it to have one to study.
 
I think you can poke out those brass terminals in the fuse box,I have never had to,so someone else here would know probably for sure..
If that can be done then you could re-solder the connector to a new wire ,and not have to replace "everything"..
 
Yeah that would be awesome if possible. I poked around with some needlenose and lightly pulled on the brass but it didn't budge
 
there will be a plastic tab hooked into a hole on the terminal, a pocket screw driver should be enough to move the tab while pulling on the wires. yup definitely a problem. see post 18 :D
 
I think this will work? I cut the burnt wire down to where there was clean copper wire, cleaned up the wiring a little bit, pulled off all of the old sheathing. I then took some new 10 gauge wire stripped it back used a solid metal Barrel crimp, then crimped it and soldered it on both ends right at the old terminal ending. Then I double heat shrink it and fabric taped it.

20200905_140554.jpg
 
Much better than bare copper!..anything is better than it was--I've been known to use wire nuts in electrical emergencies and other "jerry rigging" when I'm in a bind..


I had a '77 GMC that the previous owner put a "custom dash" in he made himself with S-W gauges & speedometer,and he did a hack job ,to power everything up he pulled the wiring harness plug out of the original dash cluster where it goes into the printed circuit ,and used brass carpet tacks shoved into the connector for the various gauges ,and just wrapped the bare wire around the tack heads,then buried it all in duct tape!..I didn't discover this till one day while plowing,I smelled wires burning..

One of the wires evidently rubbed thru against something and shorted out,not at that mess of a plug like you'd think--and it glowed red,and melted itself to the bundle of other wires,causing all kinds of back feeds and more fuse popping..
I had to take the dash right out,and rather than replace the wires that only had melted insulation, I opted instead to just separate them using a razor knife and re-wrapped them with the cloth tape you use on wounds that is waterproof for bandages (all I had at my disposal..)

I was not at home,I was plowing a parking lot and that was all the customer had--looking back that stuff held up better than most electrical tape I've used,which tends to come off and get all gooey after awhile)..it was snowing and about 20 degrees out too,and was going to get dark soon!..

I knew it was not the "right" way to fix it as the wires may have become resistors after glowing red,but everything worked OK again,it was no worse than when I got the truck,and I just used it that way for several years without a hitch..but always feared one day I'd be tooling along at 65 mph and the dash would start smoking again!..:eek:
 
Well cancel the celebration. I made sure I covered all wiring, inspected the under dash wiring and re taped it, loomed it and routed it. Ran new wiring to and from the fuse box and to the horn relay. Just bolted the fuse box back in, got it all buttoned up and reconnected the battery.

Pulled the headlight switch and POP goes the CRTSY/TL fuse. Wtf man
 
Disconnect the lighter, give the trailer plug a good look over, try again.
Check over the right side of dash courtesy wiring. Dome light wiring to, just drop the bezel down and see if wire is melty, or stuck to roof.
 
You made one rookie error. Never put everything back and close up all the covers until you test the repair.....
Wes, beat me to the next.
What he said, plus double check around where the wire was shorted. Try to see why it shorted in the first place.
In other words, what was the previous owner doing or trying to do when he put the wires in a bad place. There may have been more to that project than what you have found.
I once found a pinched wire that no one else had been able to find. They found one, but that did not solve the problem. When I walked up, I asked how the heck did that wire get pinched.
They told me that they had put on a new fender, and a couple of days later the fuse started blowing. They were looking at the originally pinched wire to see if it had burned out somewhere else.
I looked at the other end of the fender, and sure enough, they had pinched a wire up front too.......
 
GM ran those orange & white wires under the carpet near the kick panel and under rocker panel trim plate if I remember right,where they get pinched and subjected to dirt,pebbles,etc..from there they run up into the rear cab wall to the dome light..
 
Oops, I meant buttoned up the fuse box and wiring. I left the gauge cluster, dash and bezel out haha. I've made that mistake before. I did check the drivers side white/orange wiring that runs down kick panel, along weatherstripping and up and connects to the hard top plug. It appears to be all good there. I will look over the trailer wiring next after lunch. Does the courtesy light wire run up over to the B pillar inside the headliner trim? I didn't think it did. I thought interior lighting got it's power from that drivers side and through the hardtop plug.
 
It is the same feed as plug to hard top. It is spliced near the plug.
 
You must log in or register to reply here.

Latest Posts

Top Bottom