Horn wiring

[Foxx]

Hey all. I recently got an electric solenoid valve for my air horns and want to splice it into my factory horn circuit with a switch to select between the air horn and stock horn.

I found the wire under the hood at the horns. It's yellow with a green tracer. I followed the harness around the grille to a big connector on the firewall, but I couldnt find the wire again on either the inside or outside of the firewall. Ideally, I'd love to wire in my switch and do all my splicing inside the cab, instead of running a wire all the way out to the factory horn location to splice it in there. My question is, what wire do I need to look for under the dash that sends power to the horns? Does my green and yellow wire change colors in the harness or at the connector? What color wire should I look for coming out of the steering column?

Thanks!

[BlueMule]

The wire is yellow/light green from the horn to the relay and dark blue from the relay, thru the firewall and to the column.

[Twinned444]

Just take the lead straight from the horn itself for three reasons.

#1, you don't want your cheezy little electric horn running anymore when you're firing the airhorns.

#2, That wire is already relayed and ready to roll to energize a solenoid without fail.

#3, It couldn't be any easier to run. It's already tied directly to your steering wheel and routed outside for you.

Just use that very lead directly from the horn itself to energize the solenoid valve.

Works great.

Good Luck,

Steve

[Paul H]

Single wire from your switch out to the stock horn location.

Put a single pole double throw relay with one side of the coil to ground and the other side to the switch wire.

Connect the common to the original horn yellow/ green

The normaly closed terminal to original horn and the normaly open to the air horn.

Flip the switch will energize the relay and supply the air horn with the switch off the original horn will blow.