Tank29

Ok, I installed twin air-horns (purchased on-line for $80 shipped) about 18 months ago and haven't had any issues with them at all UNTIL about 2 weeks ago...One of the horns broke off and the relay mount broke off on a wheeling trip...I decided that I was just going to buy a cheap horn from Auto Zone for $20...Well, I unwired the air horn and decided to check my power...I have no 12v power at my horn connection...I can hear the relay energizing every time the horn is pressed...both fuses are good...I really have no idea where to begin looking...I have been trying to find a wiring diagram that shows the horn wiring but have not been able to locate one...If anyone could give me some ideas I would greatly appreciate it...Thanks