Sounds like you got a wire shorting out most likely someware between front of truck to the rear. Only thing to do is trace the wires along the frame until you find it, and if you got a trailer plug that would be the place to start. Or any wear it looks like someone has spliced into the taillight wires.
86 toyota with computer, won't start but sounds of relay in computer box loud, will start once in a...
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86 toyota with computer, won't start but sounds of relay in computer box loud, will start once in a while. Good battery , new starter and solenoid, and good cables to battery!
I have no power to anything in my 1986 pickup, replaced broken ground wire, there is a white wire...
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I have no power to anything in my 1986 pickup, replaced broken ground wire, there is a white wire from the battery cable that appears to have broken off of something. Don't know where it goes.