On my 59 GMC. The horn does not work either. All the original wiring is there and everything else works. I am assuming this is correct: The horn button furnishes a ground to the horn relay on the firewall, which in turn furnishes hot to the horn?
I have made sure the horn is grounded and I removed the wire, and touched a jumper hot wire to the post, and nothing happens.


57 GMC LCF 370
55 John Deere 40-W
59 John Deere 430-W
2000 GMC 4x4
56 John Deere 420-W
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