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· Registered
446 Posts
Discussion Starter · #1 · (Edited)
Shout out to @mazdaspeedmyk and his friend Matt for the help yesterday on the install! Also, shout out to @E.Tinker and @warlord for their user-friendly guides!

Of course there have been many of these to go around, but I figured I would lend a hand on an install guide, just so people know how to install these horns. BTW, these things rock. MUCH louder than the stock horn, which is all kinds of pussy to begin with. So let's start!

I used Tinker's guide, and @warlord guide on how to wire up the relay that comes with the horns. MAJOR help and huge shout out to those guys for putting in the wrench time and keeping things extremely simple.

Step 1

- Buy the horns, plain and simple!

Step 2

- The biggest aspect of the install is making sure you have the right wiring, leads, and stuff to make things look pretty. This is what you will need to purchase, besides the horns:

1.) Electrical Tape
2.) Flex Tubing (I bought a 10 foot roll, was just enough)
3.) 12 gauge wiring (I bought a 20 foot roll, was more than enough)
4.) Female Disconnects (to plug in to the relay and horns, get at least 10-20 just in case)
5.) 12 Gauge Ring Terminals (only need three, one for the chassis ground and two for the horn grounds)
6.) Help of Friends (taking off the bumper and putting it back on is a pain, don't do it alone!)

Step 3

- Measurements of the wires are huge. Here are mine:

1.) 2 feet for the relay to battery terminal connection
2.) 1 foot for the relay to chassis ground
3.) 6 feet for the relay to horn power
- You want to make sure you splice these wires, so what you would do is run a long enough wire from the relay to the first horn (horn on the bottom right facing the vehicle), then another equal length wire running from that horn to the other. I believe we used 4 feet each. When splicing, you twist each ends of the wires together, making a good tight twist, and then put that in to the end of a female disconnect that goes in to the power terminal of the horn.

Step 4

- Once you have measured, cut, and terminated each end of the wires, you are ready to start the actual install of the product. Make sure to remove the bumper, and double-check the lengths of each cable so you are not too short. If you follow my footage requirements, you should not have a problem.

Here is a picture of the wiring:

Step 5

Here is a picture of the relay. You will attach this on the driver-side of the chassis, near the wheel well. When you take off the bumper, you will see the gap and the place to put it.

- The easiest way to explain how to run the wires, and where to terminate, is to follow Warlord's guide HERE :banana 1:

- If you look at the relay picture, you can see one wire going up to the top-right. That is the battery cable.

- The one behind it that is attached to the chassis is the cable from the stock horn, enabling you to actually use it.

- The one to the left runs to the horns themselves.

- The ground was not attached in this photo, but that will have to terminate on the chassis, obviously. We drilled a hole in the chassis, but could not use it.

Step 6

- After running the wires, do NOT mount the horns. Test them first. Make sure that you have solid contact from the disconnects on to the horns, as they can slide out. Crimp them if need be. We ran in to this issue, and if a disconnect falls off, you will get a high-pitched, non-natural sound. We used a little gorilla tape to keep the leads in place.

Here is a picture of where to mount the horns:

And the horn mounted:

- If the horns sound good, and you are happy with your set up, mount them. Use stock bolts to fit in to the holes, and if you need to rotate the horn mounts (like we did), make sure to do so before mounting. This will help keep the disconnects from wiggling off the leads.


- You should be good to go! Granted this is a small mock-up writing and not the most detailed, but take it as you will. This should get you off the ground and running!


- I was lucky enough to have two others helping with the install, and who were familiar with it as they had done it before. One was awesome at wiring as well. Grab some friends for help, and learn together.
- You do not have to get anal with the wiring, but since you are mounting where the elements can affect the wiring and relay, make sure to use caution. I bought flex tubing and electrical tape to keep the wires safe. I would recommend doing the same.
- If you want it to look pretty, wrap the flex tubing around the wires, then use some electrical tape at the ends of the flex tubing to make sure it does not move.

That should about do it! If you have any questions, please feel free to reach out to me!

· Registered
446 Posts
Discussion Starter · #5 ·
Agreed with Mike. It doesn't require two people to get the job done, but having a helping hand of two during the removal and putting it back on help...same with the horns, can be done with one person but having help is always nice :)

· Premium Member
6,221 Posts
Where did you guys Ground the horns too? did you use an exsisting bolt or just drill into the bumper. I know everyone seems to ground the relay to where it is mounted im ust curious about the horns

We drilled a hole and put all the grounds next to the relay.


· Registered
27 Posts
Not sure why you removed the bumper... from being under the car it looks like there should be enough room to do this w/o that step... Thoughts?

· Da belle of da ball.
3,603 Posts
Not sure why you removed the bumper... from being under the car it looks like there should be enough room to do this w/o that step... Thoughts?

We removed the bumper so that we could mount the relay and wiring. Also, it made it easier to lay out the wiring so it was nice and tidy. It only takes 10 minutes to take off the bumper.
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