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69hugger
07-18-2020, 06:34 AM
I recently bought a '67 C-10 pickup with all LED lighting. The wiring is AAW, and the truck was professionally built. The license plate lights utilized those bolts with LEDs to illuminate the plate. Those LED bolts had been wrecked by the consignment dealer when they removed the old license plate. They twisted the wires, breaking & shorting them, causing blown fuses on the running light circuit. Their fix was to just cut the wiring to the bolts, and cap the brown supply wire. No more popped fuses.
Wanting to have license plate lights, I bought some new LED bolts (from Amazon), and figured I'd just replace the trashed ones. I tested them from the package, and they worked great. I then wired bullet connectors to them and the brown supply wire, soldering the wires to the bullets. Then covered all the connectors with shrink tubing.
When I plugged the lights into the wiring and pulled the parking light switch, instant popped fuse. I unplugged the lights, replaced the fuse, and tested the brown supply wire to ground, my test light worked fine, no popped fuse. I tested the LED lights again across a battery, and they worked fine.
My only theory is that the LEDs draw so little current is the circuit sees them as a dead short, popping the fuse.
I wonder if I need to wire in a resistor so there is more of a load on that circuit. If so, I have no idea that specs the resistor would need to be. Or the best place to get them.
Any electrical wizards that can either confirm my thought or give me another idea as to why these are causing blown fuses would be greatly appreciated.

As always, thanks in advance!!

Bill

214Chevy
07-18-2020, 05:29 PM
Sorry, I don't know anything about your wiring issue. But, I do want to see pics of that C10 though. :thankyou::flashie:

dhutton
07-18-2020, 05:47 PM
No way something drawing too little current will blow a fuse. For some reason your LED is presenting a short.

Post some pics of how you have it wired. A pic of the LED you used would be useful too. A link to the LED too.

I’m guessing the plus side of the LED is connected to the bolt itself. No idea why.

Don

69hugger
07-19-2020, 06:54 AM
I’ll have to re-address how to post pics. Haven’t done so for a few years, since the bucket debacle.

69hugger
07-30-2020, 02:38 PM
The culprit turned out to be not the license plate led bolts, but a short in a front turn signal. I found it by dumb luck.
New housing and all is golden.
Case closed.

Thanks for the interest!

moneypit68
08-06-2020, 02:53 PM
I was definitely going to say it was a short in the wiring. How’d the turn signal short out? I’d take a look and see what else is rubbing and could eventually short. Wish I did the same before I lit my Cadillac on fire as a teenager with terrible speaker wiring haha.

69hugger
08-07-2020, 04:58 AM
I was definitely going to say it was a short in the wiring. How’d the turn signal short out? I’d take a look and see what else is rubbing and could eventually short. Wish I did the same before I lit my Cadillac on fire as a teenager with terrible speaker wiring haha.

I hear that! But the truck is wired very cleanly. Not to say mistakes can't happen, but I think it was the old LED bulb/ bulb socket interface. In other words, when I wiggled the bulb in the socket, it would flicker the bulb, then blow the fuse. Finally my fiddling with it blew out the bulb. A loud pop....then a dead bulb. I cut open the socket fixture and wiring shielding. Could not see any issue. Replaced the socket assembly and the bulbs, and they now don't flicker when you wiggle the bulbs. A much more stable setup. I'm calling it good to go.
Thanks for the input. Always appreciated.

Ketzer
08-07-2020, 07:16 AM
You were lucky to find it so easily! Wiring gremlins are the absolute worst!!

69hugger
08-07-2020, 01:25 PM
You were lucky to find it so easily! Wiring gremlins are the absolute worst!!

10-4 on that. Blind dumb luck. Shoulda bought a lottery ticket that day!