Greetings --

I am a novice when it comes to car electrical systems ...

Does anyone know the specifics of the factory horn electrical connectors?
I see one multi-colored wire and one brown wire [presumed to be ground].
Is the multi-colored wire a single hot line, or is it a pair of leads in a single wire? I don't want to cut it without knowing what's in there ...


Why, you ask?

I am pondering splicing into one of the existing horn connectors and adding a third horn to the mix [ low tone] for more volume.

I don't really want to go the air horn route, and I don't really want to tear the front bumper off the car again.

Does anyone have any sage advise?

thanks!

RobsSilverMINI

 

Poke a pin into the one that you think is power, Hook a volt metrer to it and beep the horn. If you get a 12v reading, that will confirm that its power. If you don't want to cut the wire, use a scotch-lock splice.

 

Brown is the standard color for a ground wire on a MINI, so if you see a solid brown wire attached somewhere or inside of a connector, it's a ground.

 

I got a relay, a +12V ps and some swtiches from a local car store. I think I have it figured out now!

I have a spot picked out and I believe I understand how to wire up a relay to switch the new horn.

What's the best [easiest] place to hook into +12V ? Alternator? Battery positive terminal under the hood ? Fusebox?



thanks!

robc

 

I used the battery post under the hood. Don't forget an inline fuse . . .

Sounds like you have it whipped!

 

Howdy,

Thanks to the assistance of Uncle John And Greatbear, I got a third (!) horn installed in the passenger-side cowl. It's main benefit is that it is LOUD at 138 DB. I chose a Carrand "Margum Blaster" electric horn with a low tone roughly one octave below the MINI's regular low horn. Cost was <$20.00.

I added a 30A relay switched by a jumper wire tied to the existing passenger-side horn positive ( "non-brown") lead and dressed in the cables through the existing grommet at the bottom of the pass. side cowl box. See pic attached.

Uncle John recommended a fuse, and I had already decided I wanted one based on a discussion about foglights I read somewhere. Anyway I put an spade-stype fuse holder inline between the relay and the battery feed. I used a 25A fuse to protect the 30A relay.

I found some very handy add-a-connector plates at my auto store. They basically slip under your existing battery terminal [ or ground screw] bolt and provide you with three male spade connectors compatible with most crimp-on spade connectors. This made tapping the ground screw and battery jump terminal under the hood relatively easy, and I have two open pos/neg attach points left for future use. Very handy, and cheap.

Lastly I fabricated a mounting bracket for the new horn by bending one of the provided straight plates into a right-angle and adding a slight twist to enable the horn to sit nicely in the inside corner of the cowl vent, just under the vent cover. See pics attached. I did have to drill one hole in the pass. side cowl box to provide a hole through which I fastened one end of the bracket. The horn is light enough that a simple 10mm nut and lock-washer on the chassis side of the bracket suspend it firmly in the cowl opening without need any other support. It basically hovers in the right spot. : )

I made all connections and tested everything first, then firnished off by enclosing the relay and crimp-on connectors in a waterproof box, which I attached to the firewall with some 2x4" velcro strips. See pic attached. In fact this was a camper's soap carrier, cost me about $1.00. : )

End result: Three horns, great volume. The low tones are more like a 7th apart than an octave, so it has a dissonance that works well for getting attention.

The Best Part: Sonce all the wiring is done, so I can switch out the horn itself for another model with very little work.

 

lounder and cooler!!