Like Sil said, there shouldn't be relay, unless someone put one in. The horn on my 74 died of old age two years back (30 years!), and all it did was click when you hit the horn button. Alternatively, if the circuit checks out fine, you might want to hot wire the horn to the battery and see what it does. If it works, then there is not enough juice coming out of the circuit to power the horn. In that case, you might want to add an additional circuit with a relay, connected directly to the battery, and using the existing circuit as a trigger. Should work then.


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...and the bricks keep on rolling