[Scout]

Need help with my horn relay switch. When hooking up power at the battery the relay closes, contacts click closed. I can measure voltage at both wires (black & green).It measures 9.4v at the black wire in plug and 12.5v at the green. With the steering wheel off I am also measuring 9.4v running right to the horn button ring. What's up with that? Any ideas?

[jtea64]

One side of the horn relay coil is permanently connected to the positive side of the battery. The relay will close when the other side of the relay coil is grounded. Normally the coil will be connected to ground when the horn button is pushed.
Disconnect the two wire plug at the horn relay and if the relay still picks up the coil is internally grounded which means it is defective. On the other hand if the coil does not pick up, then the wire to the horn button is grounded somewhere.
Normally the horn button ring will read nearly full battery voltage when it is not grounded. You are reading 9.4v which again suggest that the relay is defective.