DIY Horn Upgrade

First, I want to thank Wheelie for showing us an easier way to replace our anemic horns.

I just completed the horn upgrade on my 2013 CX-5 GT. Total time was about an hour including a beer and smoke break.

After removing the plastic panels I realized why our horns are so weak. There is only ONE horn located on the drivers side!

cx-5-horn-6.jpg


I replaced the OEM horn with a set of PIAA Sports Horns 400/500hz.

The installation is fairly straightforward. Take your time.


cx-5-horn-1.jpg



cx-5-horn-2.jpg


These plastic pins are removed by pushing the center in first, then removing with a small bladed driver.
cx-5-horn-3.jpg


Drill out the aluminum rivets with a 1/8" bit. Be careful not to overheat the rivet or you will melt the plastic creating a larger hole. I used 9/64" aluminum rivets when reattaching the panels.
cx-5-horn-4.jpg



cx-5-horn-5.jpg


As I said, there was no passenger side horn. But there was a bracket with a ground wire.
cx-5-horn-7.jpg



cx-5-horn-9.jpg


After I cut off the drivers side horn connector I noticed it only had one wire. The horn was self-grounded to the bracket. Not to take any chances with a faulty ground, I ran the new horn ground over to the existing ground on the passenger side.
cx-5-horn-8.jpg


The PIAA horns came with two pre-made grounding straps and excellent instructions for 2 Horn/2 Wire, 2 Horn/1 Wire, and 1 Horn/1 Wire systems. Another plus with the PIAA horns is that they were Made in Japan. A nice bonus in my opinion.


 
You know after watching/listening to your video, I like the stock better.
WOW! That's an interesting reaction. The stock horn has a pecularly flat tone while the replacements are genuinly melodic. I'm considering this mod now and I really hadn't before this post. Nice job OP, and the audio quality on your little video is great! Thanks for the write-up. BTW, it's not at all uncommon for Japanese makers (especially Mazda) to use only one horn. BTW again: they're $45.38 incl. shipping on Amazon!
Update: There is an alternative 500/600hz setup with a slightly higher tone which Amazon reviewers say is more distinctive and Euro-like. I ordered that unit-$50 delivered.
 
Last edited:
There's a reverb/echo/vibration sound to it that sounds weird to me.
 
I suspect the echo/tremolo effect was an artifact of the recording and would not be heard live. But I thought it sounded kinda cool. Like an opera singer. Like Pavarotti singing "get ouuut of my WAAAAA-AAAYYYYYY"
 
I suspect the echo/tremolo effect was an artifact of the recording and would not be heard live. But I thought it sounded kinda cool. Like an opera singer. Like Pavarotti singing "get ouuut of my WAAAAA-AAAYYYYYY"

I could hear the difference distinctly between the different set-ups.

The OEM single horn was just a low tone made by Knight:

cx-5-horn-OEM.jpg
 
I'm surprised old MikeM hasn't hijacked this thread talking about how much time Mazda spent on engineering the Skyactive horn and how there is no advantage of using an aftermarket one :D
 
Shame on Mazda for cheaping out in such an obvious manner. They could at least have had their supplier delete the word "low" from the casting so that it wouldn't be quite so obvious that they didn't install the "high" to go with it!
 
But I don't get why they didn't just install the same horn they use for the new 6 on the CX-5. The horn on the new 6 has a lot more bass to it.
 
Did you replace the fuse with 20amp? I contacted WOLO Bad Boy about the one I'm going to install and he said to use the 20amp fuse.
Thanks for all the pictures. Will do the rill screens at the same time. :)
 
Is Hella or PIAA better?
I'm planning to change mine as well.

They're both good horns. It's all about what sound you want.

Did you replace the fuse with 20amp? I contacted WOLO Bad Boy about the one I'm going to install and he said to use the 20amp fuse.
Thanks for all the pictures. Will do the rill screens at the same time. :)

The Wolo is a completely different animal. I had one in my Tacoma and it required a relay. I would not install a air horn, even the Wolo, without a relay.
 
Whoa; back the truck up KnurledNut!

Went to install the PIAA 500/600 hz horns I received from Amazon just now following your instructions and quickly realized you had left out a couple of critical points. Aside from there being a few more screws and clips that needed removing (no big deal) how in the world do you get the plastic shroud out from behind the top of the grill. There seems to be some kind of lip that positions the shroud on the back side of the grill. And, once you do, how do you then get it to clear the hood release handle that runs over it? Pls answer asap as I am stuck in the middle of this project.
 
Did you replace the fuse with 20amp? I contacted WOLO Bad Boy about the one I'm going to install and he said to use the 20amp fuse.
Thanks for all the pictures. Will do the rill screens at the same time. :)

Bad advice.

Guess what happen after you replace the stock one with higher rating fuse? The weak point would be the wiring not the fuse anymore. You'll be setting your car on fire because of a horn...
 
Went to install the PIAA 500/600 hz horns I received from Amazon just now following your instructions and quickly realized you had left out a couple of critical points. Aside from there being a few more screws and clips that needed removing (no big deal) how in the world do you get the plastic shroud out from behind the top of the grill. There seems to be some kind of lip that positions the shroud on the back side of the grill. And, once you do, how do you then get it to clear the hood release handle that runs over it? Pls answer asap as I am stuck in the middle of this project.

I pulled on the grill lip then angled the shroud up and pulled it towards the engine compartment. There is some thin metal in the way but if you take your time it will work. Putting the shroud back was a challenge, but it was all in the angle.
 
I pulled on the grill lip then angled the shroud up and pulled it towards the engine compartment. There is some thin metal in the way but if you take your time it will work. Putting the shroud back was a challenge, but it was all in the angle.
Wow! Something tells me our cars were built on different planets. I struggled and struggled to deal with "thin metal" you refer to and could not do squat with it till I noticed the four vertical clips that are molded into the leading edge of the shroud and which go through the metal crossmember. The clips are released with a flat screwdriver blade which releases the shroud and leaves the crossmember behind.
 
Last edited:
Wow! Something tells me our cars were built on different planets. I struggled and struggled to deal with "thin metal" you refer to and could not do squat with it till I noticed the four vertical clips that are molded into the leading edge of the shroud and which go through the metal crossmember. The clips are released with a flat screwdriver blade which releases the shroud and leaves the crossmember behind.

Gotta love working on plastic panels. How I miss the days of metal cars.
 
I just did this mod (the principle is not new to me, since I had to do the same thing on my other car some years ago :)). Thanks to the originators of this though, for the instructions on how to get to the horn!

First, you DON'T NEED TO REPLACE the existing horn. Just add a second "Hi-note" horn on the other side - easy-peasy. I used the FIAMM 72102 "highway blaster" horn, such as this: https://www.amazon.com/dp/ (commissions earned). Though the FIAMM 72002 would probably be fine as well (cheaper, though not quite as loud). Mount it to the other side earthing bolt using the supplied bracket and earth strap on one terminal. Then splice a new wire onto the existing horn wire and run it over to the new horn side and crimp on a spade connector. Done. Wife loves it - she was complaining about the feeble horn before, now she feels 'empowered' :). By the way, I'm still using the existing fuse and it's working fine. If it blows ever, I'll revisit

I also had a lot of difficulty getting the shroud out. I managed to release the front clips to the grill and manhandle it out as one piece. But couldn't get it back in afterward. So then I unclipped the top shroud from the metal bar, put the bar back roughly in place, clipped the shroud back on to the bar and slid it in the rest of the way forward. This bit is by far the worst aspect of the mod!

One other tip... when drilling out the pop-rivets, DON'T use a 1/8" drill bit and drill though - it takes a lot of drilling and finagling to get the rivet out, plus results in a lot of kerf. Instead use a 9/64 (or maybe 5/32) bit, drill slow and it will cut the head off the rivet in about a second! DON'T PUSH, as you don't want to drill a big hole into the plastic!
 
Last edited:

Latest posts

Back