I had another stupid (on my part) short just off the ign switch and I got a beautiful pssssssff from my inner fener area and a bunch of smoke! Finally got to the bundle of fusible links and none are missing the insulation...? How can I tell if they are shot? One is soft and the insulation if loose, but none burned through.
Well, if it helps anyone else, I gave each a very slight tug and the only one that had a touch of stretch had to be it. So I pulled harder and it stretched and snapped...
I used a volt meter with the continuity test thingy... I cant remember what its called off the top of my head...
That would be the ohm tester part of the meter.
prob the wiring harness after each splice with stick pins.
turn on the car and read the voltage at the stick pin closest to the source of power with the meter.
now read the voltage on the other stick pin.
with a digital meter, there should be a voltage difference,, how much depends on the ohm rating of the shunt (fuse link).
If i were to see anything greater than a half volt, that means problems.
The wires are suppose to be direct shorts with potential to fry open and save your wiring harness from burning up. they are typically one or two wire sizes smaller than the harness they are in line with. The splices can get corroded and add to the resistance and thus increasing the voltage drop across them.
so there you have it.
easy nuff.
This is the easiest way to test them... If it comes apart with a little tug, was going to fail anyway....
yeah, I was just hoping there'd be a visual cue. I didn't want to have to probe them all. But it worked out good finding the one that was ONLY rubber by pulling...
FWIW they are designed to fry so your car doesn't burn up. I had one burn up and stay intact until I touched it and it fell apart like a long cigarette ash right befor it gets flicked off.
Right... I am just really surprised that it could completely burn up AND put out that much smoke yet leave the rubber insulation intact and virtually perfect to the eye.
Probably designed that way (theoretically). If the insulation was completely gone, the exposed end that's still connected to the battery could flop around and short out yet again.