non working air horns

Bought this used 05 Newmar 37' Kountry Star and the air horns are not working. When I turn the switch on the dash I would expect the horn would switch from honk to air horns when pushed in the center of the wheel. Nope same old standard horn honk.
I have checked the 50ampn fuse that also runs the onboard computer under the hood and it is fine. Could there be a solenoid that is out or something else to look at?

Thanks for your input.