Install guide

Compact Electric Horn

A loud, compact horn that replaces the stock horn on just about any 12V vehicle, from motorcycles to cars and trucks. The compressor is built right into the horn, so it wires up just like a factory horn. Pick the method that fits your ride and follow along.

Any 12V vehicle Motorcycles Cars & trucks
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2 wiring methods
About 20 to 30 minutes
Compact Electric Horn

First, get your horn ready

Two quick things before any wiring.

Your Compact Electric Horn has a direct drive compressor built right inside it. Take care of these two things first and it will sound great and last for years.

Don't skip this

Attach the air filter

In the box you'll find a short piece of air line and a small air filter. They install onto the intake of the horn's built-in compressor. The filter keeps dust and road debris out of the compressor, which is what keeps the horn loud and makes it last. It takes about a minute, and it's the one step people forget.

1
Push the air line onto the intake
Find the intake port on the compressor housing and press the short air line firmly onto it.
2
Fit the filter on the other end
Push the small filter onto the free end of the air line so the compressor draws air through it.
3
Point it down, away from water
Position the filter so it faces down and away from direct road spray. It needs clean, dry air, not water.
Air filter attached to the compressor intake
Mount the horn

Bolt the horn down using the built-in mounting tab. A few things to keep in mind:

  • Pick a spot protected from direct water and road spray.
  • Mount it so the air filter points down, not up.
  • Keep the front of the horn clear so the sound projects.
  • Leave room to reach the two terminals for wiring.
Compact electric horn mounted

Two ways to wire it

Same horn, two trigger options. Pick one.
Method 01 Easiest

Honk from the steering wheel

Uses the included relay harness and your factory horn button, so it honks just like stock. Two connections and you're done.

Jump to Method 01
Method 02 Custom switch

Wire it to the relay yourself

Run the horn off its own push button or toggle switch. Needs our electric horn wiring kit, or your own wire and button.

Jump to Method 02
Wire legend
Red, 10 ga
Main power & horn positive (+)
Blue, 18 ga
Trigger (+)
Black
Ground to frame (–)
Tan
30A fuse at the battery
Method 01 Easiest · most popular

Honk from the steering wheel

Use the included relay harness so your factory horn button triggers the horn, just like stock. You'll make four connections: the short red and black wires tie into your factory horn, and the long red and blue wires run to the horn itself.

1
Short red wire to factory horn (+)
Connect the short red wire to the positive (+) lead on your factory horn. Either tap that lead with a scotch-lok connector, or pull the wire off the stock horn entirely and route it to the short red wire on the relay.
2
Black wire to ground
Ground the black wire separately to clean, bare metal, or connect it to your factory horn's negative (–) wire.
3
Long red wire to horn (+)
Run the long red wire to the positive (+) terminal on the horn.
4
Blue wire to horn (–)
Run the blue wire to the negative (–) terminal on the horn.
Test it from the wheel
Press your steering wheel horn button. The compact horn honks like stock.
This horn pulls 20A at 12V. If wiring it to your steering wheel pops the factory horn fuse, switch to Method 02 below and run it straight off the battery.
If the horn honks constantly without pressing the wheel, move the black relay lead to the negative (–) lead from the OEM horn.
Method 02 Custom switch · no factory horn

Wire it to the relay yourself

Want the horn on its own push button or toggle switch instead of the factory horn? You'll need our electric horn wiring kit, or your own wire and a push button. Pull the relay out of the harness and wire its four numbered pins as shown, matching the stamped numbers to the diagram.

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1
Pin 30 to horn (+)
Run a 10 ga wire from pin 30 on the relay to the positive (+) terminal on the electric horn.
2
Pin 87 to battery (+), through the fuse
Run a 10 ga wire from pin 87 up toward the battery. Cut the fuse holder at its midpoint, strip both ends, then connect one end to the battery (+) terminal and the other end to the pin-87 wire.
3
Pin 85 to ground (–)
Run an 18 ga wire from pin 85 to the frame as a ground, or straight to the battery negative terminal.
4
Ground the horn
Run the horn's other terminal to a clean frame ground, so the horn has both power (pin 30) and a ground.
5
Pin 86 to your trigger
Option A: connect an 18 ga wire from pin 86 to the OEM factory horn positive wire, so it honks from the wheel.
Option B: connect pin 86 to one leg of the push button, and the button's other leg to a +12V key-power source. The horn honks when you press the button.
6
Install the fuse
Insert one of the tan 30A fuses into the fuse holder at the battery.
Test it
Press the steering wheel (Option A) or the push button (Option B). It should honk every time.
Troubleshooting

If something's off

No honk at all

Check the fuse first. Then confirm your ground lands on clean, bare metal, not paint, and that the red wire has power when you press the button.

It pops your factory horn fuse

The horn pulls 20A, which is more than most factory horn circuits like. Wire it with Method 02, straight off the battery through the included 30A fuse.

Honks nonstop

On Method 01, move the black relay lead to the negative (–) lead from the OEM horn. On Method 02, recheck pin 86, the trigger wire is seeing constant +12V.

Your horn triggers on negative

Most factory horns are positive-trigger. If yours triggers on the negative side, run the horn power directly and use Method 02 with a push button instead of tapping the factory wire.

Sounds weak or strained

Make sure the air filter and air line are attached to the intake and the filter isn't clogged or blocked. A starved compressor sounds weak.

A wire works loose later

A weak crimp or scotch-lok backs out over time. Make sure every connection is solid, and re-do any that feel loose.

Stuck mid-install?

Our Tampa crew wires these every day. Send a photo of your setup and we'll point you the right way.

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