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1970 Indicator Fuse keep blowing

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sabre:

--- Quote from: Matt G on December 30, 2017, 09:21:06 AM ---
I thought more on the headlight scenario, and scared myself with some logic...  That being: If I'm popping fuses (pretty violent fuse wire burn on inspection of spent fuses), then if I allow that current to flow (through a headlight), I'd essentially be passing bucket loads of current through wires that my fuse is trying to protect.  I'm just a wee bit scared that dust, old wires, fibreglass and Murphy' law means that I stand a good chance of melting a wire in the wrong spot potentially giving my wife her corvette insurance money dream...
Feedback and ideas (as always) are really appreciated.

--- End quote ---
Hi Matt
The idea of the headlight is to both give an indication of the current flowing (full on - there's a short, dim - normal load) and to limit the current flowing. A normal 60W headlight will limit current to 5A even if there is a dead short. Since a headlight circuit is usually designed to handle 15 to 25 A, the headlight will protect the wiring. It's an old trick. The only thing you should be aware of is that the flashers will run slow because of the reduced voltage dropping across the light.
I'd be looking closely around the tail light wiring too. The original flashers used the brake lights. Normally a new wire is added for the brakes and original wires kept for the flashers. I've seen some pretty dodgy splices doing this.

Matt G:
Thanks a bunch Sabre. The headlight logic makes sense. I'll check the rear wiring, but I think it's more likely to be in my steering column/dash. I had some repairs done a few months ago, and I know that he had to drop the steering and pull the driver's dash cluster.  I'm leaning towards him pinching the series of wires that run bottom side of my steering column. I'll definitely hook up a light.

Vettech:
Yes Sabre I forgot about that, the extra wire to the rear to divide the brake and flashers.

Worth a look, esp if you can put a test lamp or buzzer and get under the rear and wiggle.

However, I used to work Maint along side of construction (NDC) staff, and 89% of faults were caused by their work.
Now you have mentioned some one else working on it, as a suspicious mongrel I would immediately suspect him/her.

Matt G:
Got it. Thanks guys. I'll check the rear (pretty easy with a good light and some persistence...).  I got my wiring diagram stitched together. Might be a few drinks before I manage to join the dots, and then a few more before I figure it all out...

Matt G:
Hey guys. Massive, massive thanks to Garry/Sabre. After almost a couple of hours of jiggling wires, looms and connections while watching the test bulb, and with Garry's fantastic experience (and work pit), we found the short via my back-up switch wires that had burnt through on my exhaust and randomly grounded on the flange of my headers.  A huge help. Thanks again Garry. I hope to be able to return the favour one day, or similarly help another member.  For me, this type of help and experience is what it's all about...
cheers to all who volunteered experience and help!!🍺

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