How to test the horn

gdizzle said
ok horn works loud when directly connected to battery. It is already grounded by the mounting so all I had to do was touch a wire from terminal to battery +.

So if horn works, how can I determine if horn relay is bad?

Access the column connector, the horn button wire, and ground it with a probe. You can also do so at the relay, the small black wire.

You do have? by now? a shop manual.