M3 HB horn location?
 

I want to replace the factory horns with something that sounds a bit more substantial. Did this on my Toyota pickup, & what a difference! People now pay attention. But where are the little beepers? Expected them to be in front of the radiator, but couldn't see them Thanks, JeffD

Check this:
https://www.mazda3club.com/showthrea...highlight=horn

I believe it is somewhere under the left headlight. Let me know what horn you'll be using as I might be interested in doing the same :)

Good Luck!

The horn (singular) is located behind and slightly above the driver's side fog light. Access is easiest if you can put the front of the car on jackstands or ramps ( I wouldn't suggest the stock jack for working under the car), unscrew the screws holding in the plastic baffle and look up and you'll see it.

There are lots of options for replacing it. I have dual tone Fiamm Freeway Blasters installed and they sound great. The run about $30 for the pair and the install is relatively simple. Other horns that people have used are hella supertones (~$50), Wolo horns, and the stebel nautilus compact dual-tone air horn. (~$50)

Personally if I were to do it again I would put in the stebel. The reason for that is.... well, it's an air horn the size of two cans of redbull. Plus if you wire it through the stock wiring vs. using the relay it comes with then when you hit the lock button twice for the horn confirmation it sends such a short burst of power to the compressor than instead of a full force blast you get a little chirp. I'd personally prefer that myself.

If you want more details and/or pictures for installation let me know and I can get some together for you.

I've been meaning to replace my stock horn but i haven't had time...or money for that matter...but yeah its where icspots said...i found it by accident...i used car ramps to get under it...they're pretty stable. But i wouldn't use the stock jack either

Horn's replacement found
 

Thanks IVO,and to all for thier input. After ck'ng out the many suggestions I'm going to order one of the Stebel Nautilus Compact Dual-Tone 12-Volt Air Horns. Found it for sale for $32.99 at Cas Sport Touring (<http://www.casporttouring.com/>) Scotteast's behind- the-grille mounting solution looks really clean. Now to figure out to remove the grille. Any special tools needed? JeffD

If you're mounting it behind the grill then you'll need to find a bolt to connect it to, also you'll need to extend the wiring from the stock horn up to that location. If you decide to leave it in the stock location then it should go in pretty easily.

Are you going to use the relay, or the stock wiring so you can get the confirmation chirp? If you go that way double check the fuse..... I believe the stock horn has a 15a fuse.

Replacement horn mounting
 

IVO, thanks for the 'fuse' heads-up. Will definitely ck it. Would this necessitate a higher value fuse? Yes, I'm going to use the stock wiring, with an extension if necessary. I do want to keep the 'chirp'.
Got confirmation on my horn order this morning, totaled out at $40.43 w/shpng and Ca sales tax..
Was wondering about that behind-the-grille mount. Most of the M3's supports there appear to be made of composites, not metal. Grounding would be an important issue.

If you're just hitting the horn for short bursts (vs. holding it in for a long period of time) then popping the fuse shouldn't be a problem. If you do find yourself popping it then try upping it to a 20 amp fuse instead and see how that does.

IIRC most of the mounts are plastic, however if you're running a wire to the stock wiring then just run a ground wire there as well and ground to the stock horn bracket.

I just got one of thew Stebel Nautilus compacts for my brother for his '08 3....I'm going to do the install. It seems that the relay is a 30A....even increasing it to 20A seems like it's not enough, but what gauge is the current wiring and can it handle 30A through it? What is the result with the "chirp" if I use the provided Stebel relay?

For short burst of the horn you should be fine with the stock wiring. If you're planning on holding the horn down constantly for long periods of time then you should hook up the relay. If you find yourself popping the fuse a bunch then you can: A) replace the fuse in the fusebox with a higher rated fuse, B) put an inline fuse for the stebel as an extra precaution.

AFAIK if you hook up the horn with the relay harness then you won't get the chirp with lock confirmation. The reason for the chirp is the lock conf. sends a very short, low power burst to the horn. This burst is too little/short to get the compressor going all the way so it doesn't wind up enough to give a full blast. With the relay installed the relay is still going to "open" all the way even with a short burst, so it should give full power to the horn straight from the battery while it's "open".

You can pull the front bumper off in about 10-15 min.If you do this, you will have lots of room to move around and it makes it very easy to install. I took mine front bumper off to install my CAI thats when I saw the horn, so I decided it was time to upgrade it. Very easy to do!!!!