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Discussion Starter #1
on my drive home I had some smell from under the dash I pulled over and checked everything, found the tail light fuse blown and the harness steering colum connector hot. I got the car home and started searching for a possible ground, disconnected the neg bat cable and put a test light in the neg side the test light came on, I started diconnecting plugs until the light went out but its not being consistent first the light went out when I disonnected the flat harness I plugged everything back in to go thru it again only this time when I disconnected the headlight switch it went out, there is a black/orange wire that goes to both of those switches I am thinking that is grounding some do you think I am on the right track here? when I pull the tail lamp fuse the light goes out.
 

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I'm a little lost on why the tail light fuse popped and the turn signal wires also got hot. Maybe something around one of the outside lamps. Try unplugging the rear lamp harness and/or the front turn signal lamps in the bumper and see what you get.
 

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Discussion Starter #3
well I have the dash ripped apart there is an orange and black wire that runs to the brake switch that melted down today and melted into the black and white wire that also goes to the brake switch I pulled back all the tape and made sure there were no other bad wires I am going to have to replace those two obviously but I am still getting a ground witch will go away when the flat harness that runs to the trunk is unplugged. I plan on getting a new brake switch, flasher and turn signal switch anyway. the harness gets hot when the brake pedal is down and the colum is connected what do you think caused it to all the sudden melt down?
 

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You unplugged the flat harness to the trunk and got some positive results. I suggested to unplug the tail light harness from the other end of the flat harness. Taking a stab might be something back on the tail light harness.
 

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Common problem with the older car wiring harnesses.
You start building resistance somewhere in the system,older wiring insulation is on the weak side. Sonn resistance starts really heating the wires & soon th einsulation melts and causes a gamut of trouble.
Call M& H Fabricators and order new harnesses.
I've seen too many melted original harnesses to ever trust one again. I replace all my harnesses when doing a resto regardless of how good it looks.
 

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Discussion Starter #7
I started pricing new harnesses last night I definatly need one but I am going to have to patch this one up until I get to my new home in LA. I have some things to go on now , all I need to do is go home and try it.
 

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Still sticking with one of my original guesses. Unplug the tail light harness.

Finally got some time to look at the schematic so I might have an idea what's going on. The black/orange is a BAT output out of the fuse block. It's fused but always hot as long as the battery is connected. It runs or feeds both the brake switch and the tail light circuit through the head light switch (You knew all that I imagine).

1, White/black is the output wire from the brake switch to the turn signal switch.
2, Both black/orange and white/black are melted at the brake switch.
3, Turn signal connector gets hot.
4, Unplugging harness to the rear appears to eliminate the problem.
5, Stepping on the brake heats up the wires.

The black/orange is also in that cable to supply power to the dome light. I don't think that's the problem. Otherwise the problem would occur without stepping on the brakes. Believe the problem is related to the yellow or the green wires to the brake lights. Out on a limb again, I won't first suspect the harness to the rear as the first guess. More likely something back on the tail light harness. A partially shorted light bulb can cause this or a partially damaged harness. With luck, the harnesses weren't permanently damaged. Not sure if that harness under the carpet is available.
 

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Discussion Starter #9
its fixed! I replaced the bad wires and found a bad socket in the drivers tail light. after I changed everything out I hooked up the battery and left the brake lights on for several minutes, nothing got hot and no fuses blew. I am still going to replace the harness but at least I can drive the car on my vacation/move. thanks for all your help
 
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