Fiaam 128DB 12V Air Horns on a 2nd Gen 4Runner
11/25/2002

Joey (UKMyers on the forums) shows you how he put some after market air horns on his 4Runner to command some respect while in traffic.
The stock Toyota horns leave much to be desired in the tooting department.

This is a pretty easy mod to do and if you are looking to get peoples attention when you need your horn this will definitely do the trick. I ordered mine online from JC Whitney for $23.99.

Materials Needed:
Approximately 4 feet of wire( I used 17amp)
Basic connector to use for your ground
Butt connector to tap into existing horn wire
2 Spade connectors for the compressor plugs
20 Amp fuse
Basic Tools i.e. screwdrivers, side cutters, socket set
Drill and 1/8” bit
Approximate time to complete: 1 Hour

The first step of the install was insuring that they would fit under the hood. Two brackets come with the horns to mount them separately but due to lack of space I just sanded a flat spot on the smaller trumpet and zip tied the two horns together. With this setup you only have to drill one hole and they take up less space.

Next I found a suitable place for the compressor and used the other horn bracket for it. The kit supplies a large bolt that you are supposed to use on the compressor but you have to have somewhere to use a nut on it and with my mounting set up that would not work. Using the bracket and drilling a hole on the inside of the fender was much easier to mount it.

Once I knew the stuff would fit fine it was time to do the wiring. The kit supplies a wiring diagram and a relay but NO wiring. After reading JasonB’s write-up I decided against the complicated relay set up and to just tap right into the existing horn wire. The factory horns are right behind the grill. They have one 12mm bolt holding them to the truck. I just undid this and unplugged the plug on the horn. (NOTE: All of this is a pain to do with the grill in place, as working space is limited but I found that removing the grill is even more of a pain. I gave up after a while for fear of breaking it.) The following task can be done with the grill in place it's just tedious. With the plug undone I just tapped into the existing wire using a butt connector. After confirming I had power to my new wire using a voltmeter all I had left to do was route the wire back to the compressor. Note: The wire on the existing horn is only hot when the horn is honked. I routed the power wire behind the grill and then through a hole behind the headlight and up the inside of the fender to the compressor.

All that is left now is final assembly. To mount the horns I drilled a hole in the fender well and used a ½” sheet metal screw. I also used this screw as the ground for the compressor. Next I crimped the spade connectors to the end of the new power wire and ground, plugged them into the compressor and used another sheet metal screw to mount the compressor. The last thing to do is make the air lines, which is pretty simple to do using the supplied Y and clear tubing. After tidying up the wiring with some zip ties I was done!

The last thing to do is test these bad boys out. They sound great and the bonus is the old horns still work as well. You will get noticed when you lay on these things.
Here is a sound clip of the horns 
Also if for some reason you need them disconnected all you have to do is unhook the ground on the compressor and your back to the old stock road runner horns.

If you choose to do this mod good luck and if you have any questions  (UKMyers) on the Yotatech Forum.

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