Horns

The passenger side horn on my Avy does not work.  I unplugged it and hooked it up to a battery and nothing.  Is the passenger side horn tone high or low?  I've only been able to find this one that states it is low.  Is this the correct part? 

http://www.carparts.com/details/Chevrolet/Avalanche+1500/Replacement/Horn/2005/REPC502501.html

(1) Radiator Support
(2) Horn - High Note
(3) Horn - Low Note

Do you have a part number?

I really don't like giving out part numbers because they always get revised, but here is something to get you started.