Second project was installation of my air horn.
I used the same bracket that I made for my battery tender, just bent in reverse. Battery tender is on the left side of the truck, air horn is on the right. I made a diagonal support for the end of the horn. It's 18" long, so it needed some support.
Powder coated the brackets.
Installed the horn behind the front-right corner of the bumper. Sorry for the crappy picture - difficult position to get a good photo. This is taken from laying on the ground looking up into the bumper area. The horn is installed just below the fog light. Hard to see in this picture, but the air horn is aimed out of the tow hook hole in the bumper.
I made a small PDC with 2 fuses and 2 relays that ties into the VSIM under the dash. The first relay provides conditional control - the air horn will only work when the truck is running and the horn button on the steering wheel is pressed. That way I don't blast myself and my neighbors every time I lock my truck. The second relay ties into the "wig wag" feature of the high beams and tail lights. When the air horn is enabled, so are the wig wags. When I honk my horn, I also flash. I also installed an enable/disable switch on the steering column boot. It's just below the pedal adjustment cover, and in front of the tilt adjust lever. That switch has to be on for the air horn to work. Sometimes, you need to give a friendly honk.
The PDC under the dash outputs a single wire - a trigger wire to the relay that controls the air horn (mounted with the air horn behind the front bumper). I routed the wire through the firewall through a small phallic looking protrusion in the main wiring harness boot. This is a view from under the dash. I left the wire exposed in this photo for clarity, but it's wrapped in fabric electrical tape now.
The wire comes out in a really difficult place to get to (and photograph). Again, the wire is exposed for clarity. I had to remove the OE auxiliary fuse box (diesels and Aux switch) to be able to get to the wire.
Overall, the horn sounds pretty good. It's not as loud as I'd like, but that will change once I install my on-board air system. But I like that it has a lower tone then some of the triple horn kits with short trumpets. I wired it to operate in conjunction with the OE horns just for some extra volume and higher tones.
