Train Horn Wiring Question

[rm17742]

Hey guys,m

I have a quick question. I was installing my new train horn on an early '99 F-250 last night and I ran into a snag. I want to use my factory horn "button" with a toggle switch so that I can go between my stock horn and my train horn without an additional button.

My question is:

Does anyone know what color the horn wire is on an early '99? I have seen in a couple of previous posts where guys tapped into a yellow wire with a green tracer. Mine is not that color (at least that I can find under the dash). I would really appreciate if someone could give me a hand if you have a wiring diagram or just general knowledge.

I will post pictures / video when I get done.

Thanks!

===Russell

[BOILERTURF2387]

I'm not sure on the color, but najaf4life did what you are wanting to do with the toggle switch. Shoot him a PM and see if he remembers. GOOD LUCK

[rednekexprez]

just go to the horn and follow the wire back as far as ya can and tap it there..thats what I did..

[rm17742]

I would, but it is painful to get to. I was trying to see if anyone already knew what color it was. Thanks!

[rm17742]

I found a solid dark blue wire underneath the dash that has 12 volts until the horn is depressed. When you blow the factory horn this wire drops to 0 volts. I am sure this is hooked to the horn relay. Does anyone know if I can use a relay from here to energize the train horn? Any other thoughts?

Thanks!

===Russell

[sikktruk01]

yes the terminal #87 on the horn relay is what i used, just hook your air horn trigger wire to that terminal and install a switch on/off switch, then you can choose either the factory horn or factory with train horns. I think it's relay # 3 in the under dash fusebox