Electrical troubles
J-Ri
01-06-2005, 01:59 AM
I took my 86 Silverado through some water (deeper than the intake :-\) and I've been having electrical problems since then. I blew 2 fuses (radio and instrument cluster), after I replaced them, the truck was fine for about 6 months. In that 46 months it was sitting in an outdoor storage facility, being driven every 2 weeks to a month.
After about 4 months, I went to start it one day and it had no power to anything but the headlights and horn. I checked a few things out, and concluded the ignition switch was bad. I replaced the switch, but it didn't fix the problem. I discovered that by puting 12 volts to the ignition fuse, I could simulate the key being in the "on" position. Now I'm thinking that perhaps a rodent got inside the dash and had a feast on my wires insulation, and the one that supplies power to the ignition switch is shorted to ground, although I have found no wires with chewed insulation. With 12 volts to the battery side of the fuse, the fuse will blow within seconds of starting. With 12 volts to the other side of the fuse, it will run fine most of the time. The wire I have supplying power jumps from the battery side of the horn fuse to the fused side of the ignition circuit. That worked fine for about a month, but one day smoke started pouring out from underneath the dash. I pulled the jumper wire out and it was completely striped of insulation, and it had melted plastic from the fuse block on the ends.
If the wire is connected, everything is completely normal. If the wire is disconnected, or when the fuse blows, the voltage jumps WAY up, well over the top of the guage. The oil pressure and water temp guages are also off.
what does everyone think could be causing that?
After about 4 months, I went to start it one day and it had no power to anything but the headlights and horn. I checked a few things out, and concluded the ignition switch was bad. I replaced the switch, but it didn't fix the problem. I discovered that by puting 12 volts to the ignition fuse, I could simulate the key being in the "on" position. Now I'm thinking that perhaps a rodent got inside the dash and had a feast on my wires insulation, and the one that supplies power to the ignition switch is shorted to ground, although I have found no wires with chewed insulation. With 12 volts to the battery side of the fuse, the fuse will blow within seconds of starting. With 12 volts to the other side of the fuse, it will run fine most of the time. The wire I have supplying power jumps from the battery side of the horn fuse to the fused side of the ignition circuit. That worked fine for about a month, but one day smoke started pouring out from underneath the dash. I pulled the jumper wire out and it was completely striped of insulation, and it had melted plastic from the fuse block on the ends.
If the wire is connected, everything is completely normal. If the wire is disconnected, or when the fuse blows, the voltage jumps WAY up, well over the top of the guage. The oil pressure and water temp guages are also off.
what does everyone think could be causing that?
planedude
01-06-2005, 02:14 PM
check your conection on the starter, this has been know to cause alot of issues.
J-Ri
01-06-2005, 11:22 PM
Thanks for the reply. I fixed the problem this morning, turned out a fusible link to an isolated 12v stud... powers the ignition switch, power brake unit, alternator, and 3 other wires that I didn't trace. If the alternator doesn't have power going to one of the terminals, the output voltage is way too high...
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