As long as I've had my '92 FJ (since 2005) the horn has been somewhat...lackluster. At idle or with the engine turned off it sounded like a dying baby lamb, that is if you could actually hear it. So I finally got off my sorry ass and installed a relay to power the horn(s) and it is much better, although I may now upgrade to something with a little more horsepower or more correctly, more dB. While working on it I got the bright idea to wire my aux lights through the NC contact of the relay so that they are normally on and every time I honk the horn I am also flashing the aux lights. If they hear and see you, that much better!
Here's the relay tucked nicely under the tank.
(http://fjowners.com/gallery/7/112_20_09_14_6_17_09.jpeg)
And here's the horn/light combo in action.
https://www.youtube.com/watch?v=QkuHyay9kKM
Zwartie