The Stovebolt Site Forums The Shop Area The Electrical Bay Brake light, tail light, horn electrical issue.

1. Can you confirm that when you drove it that all lights and horn and gauges were working? Before you started messing with wires?
2. I would not assume any of the wiring is correct or all is original.
3. We will not be able to answer your question as to if you did or did not cause anything. Does not matter.
4. This must be handled one step at a time. Sort of, one issue/circuit at a time.
5. The diagnosis will be suggested by asking you questions and having you do tests, one step at a time. You will not need to ohm anything. Just need an ice pic volt tester.
Firing off guesses is not how to troubleshoot,
Assume it is 6V and no non stock electrical stuff.

"When I removed wiring from components in the engine compartment, and on the right fender, I did label the wires." What were you actually doing? and why?
You should NEVER play with wiring without taking negative cable off of battery.

In 46 there is only one fuse and that is built-in to the headlight switch. Looks like headlights and park lights wires run toward the left front, spliced to right side. Left continues to a terminal block for light servicing. Right side wires go to same type terminal block for service.

In general you will just examine where there is 6V and where there is not. Operating switches off/on as you test, Let us knoe where voltage is and where it is not so we can think on it. Don't do anything else for now. Don't change anything. Likely you have several issues at once. 46 is a very simple wiring diagram. Few wires. We will be able to help you all the way if you wish.

You may eventually find old broken wires and terminations, PO mis wires, bad switches, bad bulbs, and GROUNDING ISSUES. The whole truck is the ground return path for everything and all those ground connections are 79 years old.

It seems you said you touched the two horn wires together before hooking them to the horn. One of them is a hot wire and the other gets grounded by horn button. So there would be no spark. You may have touched the hot wire to a ground or the horn body.
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