Installing New Horn

[Nolanontheriver]

Hi,

New Defender owner here (D90 2014 MY). In an effort to learn as much about it as possible, I want to take on some small projects. 1st off the block is installing a new horn. I don't want to effect the main horn, for roadworthy reasons, so will install a 2nd air horn.

Have found a compact model made by Stebel Nautilus, which has the compressor built in, and have read through basic installs and diagrams online(no prior electrical knowledge).

My first question is, does it have to be connected directly to the battery terminal, or can the power come from the fuse box? All how-to's i've seen online show the horn wired directly to the battery, which seems a bit sloppy.

Has anyone installed an air horn in their Defender, and have any tips or tricks I may have overlooked?

Thanks,

Nolan

[Toxic_Avenger]

I've installed a stebel nautilus in another vehicle but I replaced the original horn with it. It was a straight plug and play deal.

IIRC they draw more current than a normal horn so there is a risk that they might burn out the fuse or switch in some vehicles. If you are looking for an easy install as a standalone accessory, just hook a decent size wire from the battery to a suitable fuse then to a momentary switch which can handle 20A. Run the positive out of the switch, to the horn then earth the other pin on the horn somewhere on the vehicle body. You can get way more involved with relays and other wiring tomfoolery, but might not be worth the effort for the few times a year you use the 120dB loud horn!

[rovers4]

A couple of things to check, or decide upon:

Do you want the two horns to sound together? If so, you'll need to run a relay, preferably supplying both horns. Power it from the battery as said, with a decent fuse. Make sure your new wiring is of a suitable capacity.

BUT:

In your state, can you legally fit an air horn?

Can you use them in built-up areas?

rovers4

[Toxic_Avenger]

In short, yes air horns are OK as long as it does not emulate a siren (2 tone). Sadly horns that play the godfather tune or Dixie are not allowed :o

The answer you seek is in ADR 42/04

Particualrly section 20:


20. WARNING DEVICES - AUDIBLE

20.1. General

20.1.1. No siren, repeater horn, bell, exhaust whistle or compression whistle or other device capable of producing a sound resembling that produced by any such siren, repeater horn, bell or whistle must be attached to a motor vehicle other than an emergency community service vehicle.

20.1.2. For the purpose of this clause, a repeater horn is any device which generates an audible sound (to be emitted) alternating between different tones or frequencies on a regular time cycle.

20.2. Warning Device

Every motor vehicle must be fitted with a least one warning device capable of giving sufficient audible warning of the presence of the vehicle. It must give an audible signal having constant amplitude and frequency characteristics. It may be powered by any energy source including compressed air.

[ThorneGator]

I recently put a stebel in. Used existing wiring with upgraded relay (supplied with horn), and have had no issues. That being said, there were a couple challenges...
First, there are two horns in there (one for the alarm, one for the normal horn). I used a Haynes Manual wiring diagram to ID the correct one. The normal horn ended up being mounted between the headlight and the side-wing, while the alarm horn is mounted between the headlight and the radiator.
Second, to mount the stebel, I had to bend a piece of aluminium angle to allow the larger stebel to fit in place of the OEM horn. Hope this helps

[technophile]

I have installed the stebel horn also, it is great. As for wiring, yeah wire to a fuse box, and use the included relay.

You can also remote mount the air intake for the horn if it is somewhere it may get wet.