Hey ROBERT S. JACKSON,
Just to confirm you have checked power and ground at both horns when operated with a test light/multi-meter?
If you have checked these the next step I would advise is checking for power input from the horn switch at the relay.
Let me know if you have access to a test light/multi-meter and what you have checked and I will let you know where to go next.
Saturday, March 23rd, 2019 AT 6:46 PM