86 K10 smoking under dash.

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tpangle85

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Indian Land, SC
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Travis
Truck Year
1986
Truck Model
K10
Engine Size
5.0
Just went to take my son to practice last night and there was quite a bit of smoking coming from under the dash. Disconnected the battery for now and found the dash lights and the radio were not working when I had a quick second to check it. The 15 amp radio fuse was blown. I tried another one and the radio came on and started working and then blew the fuse a few minutes later. Is the radio on these trucks the only thing on the radio fuse? Or are dash lights powered by it. My manual isn't showing a very good wiring diagram and I really don't want to burn my truck to the ground. Anybody have a good wiring diagram?
 

tpangle85

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Travis
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1986
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K10
Engine Size
5.0
I wish it were just a cigarette LOL. It'd be a lot easier to fix. Well if they're on the tail light circuit then I have separate problems as I suspected because the tail lights were still working. Maybe I let the smoke out of the light switch, if only I knew how to reinstall the smoke
 

fast 99

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Smoke makes everything work when it's let out something doesn't work.

If a lot of smoke, there should be evidence of hot wires or connectors.
 

Turbo4whl

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You can buy smoke fluid, but you need a machine to install it.

You must be registered for see images attach


Power comes to the headlight switch from 3 circuits. The tail light fuse. The dome light/cigarette fuse and one un-fused wire for the headlights. There is a circuit breaker in the headlight switch for the headlights.

Gremlins, like mice, like to chew on wires to sharpen their constant growing teeth. Old age and dried out wire insulation can just bust off. Be careful finding the problem.

The headlight switch has a ground wire to turn on the dome light. If the old plug on the headlight switch breaks apart, the plug it's self can smoke.
 

RustyPile

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I've used this tool for 50 years.. Never failed to locate a short using it..

 

SirRobyn0

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1984
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C20
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305
So about 10 years ago I bought a 1977 Cadillac. On my way home from Portland (about a 200 mile drive) smoke started pouring out of the steering column. It actually did this twice on the drive early on and it was so bad it would burn my eyes and nose. After I got it home I drove it around locally and did some other work. It's never done that again. IDK what the smoking was all about. Not very helpful to the OP but just an odd story I suppose.
 

Radiohead

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I've used this tool for 50 years.. Never failed to locate a short using it..


Ooh, gotta get me one of those
 

Ricko1966

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Replace the fuse with a 194 bulb. I dont have a pic on this phone, but I clipped the socket with bulb from a parts car. I crimped a 1/4. Male terminal on each lead. Plug it in in place of the fuse turn everything in the truck off, then start disconnecting electrical components and shaking wires the light will go out when you find your draw, it will flicker. when you wiggle the offending harness. But the bulb is an electrical load, so it is a complete circuit, meaning, you wont burn the truck down. And its nice not having to burn 1000 fuses.
 

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