Horn not working Ducati S2R 05

[Ducatiloo]

I had a 2005 S2R.  My horn is no longer working, I tried my stock and my aftermarket nautilus horn.  I've tested both any they honk without issue, yet neither when set up as intended work.   

Things I have checked / changed
1) The horn fuse
2) The horn switch. My old one didn't work so I bought a "new"  left controls that has tested ok.
3) I have tested every wire and all showed that they could carry a current.
4) The relay for the nautilus horn.
5) Verified that both horns I have tried actually work.

All test ok but not a peep.  This is driving me crazy any thoughts or ideas?

[He Man]

Strange, EXACT same problem with me i tested both my horns and both work. the relay is working, but when i hook it up it doesnt work. checked hte wireing and re soldered eveyrthing. i checked my fuses too. no idea whats wrong.

[Ducatiloo]

I keep repeating the same steps muttering to my self "this isn't that complicated" 

[Howie]

Check that you have a good ground (black wire).

[He Man]

Mine is grounded to the frame and has a good connection. sanded down the connector and all.'

[Ducatiloo]

Mine is grounded to the frame and has a good connection. sanded down the connector and all.'

+1 I used a wire brush to clean the connection.