This after market horn thing

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Can someone explain to me why an aftermarket horn like a Denali can’t be just wired to the wire that the existing horn is wired too? I had a Denali on my 701 and it was just a case of unplugging the old horn and plugging in the Denali. Now nippy Norman sells a cable https://www.nippynormans.com/horns-and-accessories/horn-wiring-kit-for-bmw-bikes-with-can-bus-wiring That is for wiring in a different horn, why can’t I just swap horns for a Denali, all it is is an electrical current? Or does this wiring kit have to be used as well as your stock horn. Can’t see the point of having them both.
 
Because your bike no longer has a traditional wiring loom. It now has a canbus system which is sensitive to electrical current. A Denali draws more current than a stock horn and the Canbus doesn't like that ... :thumb2
 
The can bus is set up to see a certain current load when the oe horn is operated. The aftermarket horn draws more current so when the can bus sees a higher reading it shuts down the power as it assumes there is a fault.
It is the same principle as the accessory socket which shuts down above 5 amps.

As dibble above has noted, but his is a lucky guess :D
 
So you can’t swap horns then, you have to add one?
 
So the kit that nippy sells how does that work? It looks like it plugs into an existing accessory port which is fine but how does it know when you press the horn button?
 
So you can’t swap horns then, you have to add one?

I would think that lead plugs in to the plug going to your horn which then gives you the siganls you can use to wire in a relay to operate the aftermarket one.
 
That’s not really plug and play then like it says. I have a hexcan but don’t want to waste a output on a horn. I just had a Denali left over and was seeing if I could use it.
 
The can bus is set up to see a certain current load when the oe horn is operated. The aftermarket horn draws more current so when the can bus sees a higher reading it shuts down the power as it assumes there is a fault.
It is the same principle as the accessory socket which shuts down above 5 amps.

As dibble above has noted, but his is a lucky guess :D

Dibble ! Brilliant !!
 
That’s not really plug and play then like it says. I have a hexcan but don’t want to waste a output on a horn. I just had a Denali left over and was seeing if I could use it.

If you are unsure and need any help send me a pm as auto electrics is my business :thumb2 Ignore any smart arse comments from Giles :blagblah
 
If you are unsure and need any help send me a pm as auto electrics is my business :thumb2 Ignore any smart arse comments from Giles :blagblah

My lips are sealed ......

<a href="https://gileslamb.smugmug.com/Backtoschool/i-SZHB7Zx/A"><img src="https://photos.smugmug.com/Backtoschool/i-SZHB7Zx/0/02a18337/O/chimp2.jpg" alt=""></a>
 
There's a bloke on Youtube making a hash of fitting a much louder 5 series horn to his GSA. Whilst he failed because he couldn't adapt the way it fitted (upside down) when he just bolted on, the electrical connector was identical (making it "plug and play" in that respect) and it worked with the canbus. Someone with a bit of engineering nouse could probably have adapted and overcome I'd have thought.
 
That’s not really plug and play then like it says. I have a hexcan but don’t want to waste a output on a horn. I just had a Denali left over and was seeing if I could use it.

If you change your mind, I can report the horn and ezcan works perfect
 
It is only a matter of time.............I think the hippy is a secret agent :rob sending you the hoody was planting a seed :p

Indeed. I certainly can see the resemblance between myself and Jackson Teller ....

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That’s not really plug and play then like it says. I have a hexcan but don’t want to waste a output on a horn. I just had a Denali left over and was seeing if I could use it.

You can't really use the horn output for anything else anyway as it only outputs 12V while you have the horn button pressed, and there doesn't seem to be a channel configuration which doesn't include a horn, except for configuration 1, and this rather wastefully uses two outputs for the lights, so you are no better off. You could drive both lights off one channel to free up the other, but the unused light channel would get its voltage reduced if you used the dimmer control on the lights, or get disabled if you switched the lights off, so that's not much use for anything else either.

I think the software should let you set up your own channel mapping, but unless I have missed something, it seems like we are not trusted to do that!

For this reason, after recently acquiring a HexEzcan to replace my Fuzeblock, I decided I might as well use the horn output. This allowed me to take my second horn off the relay I had it on, which tidied up my wiring quite a bit. I use configuration 4 and run both my auxiliary lights off one channel. I use one channel for powering two 12V to USB adapters, which leaves just the brake light channel free.

I ripped apart my secondary brake light, which fits on my Shad top case mounting plate, and removed the original bulbs from inside the fitting and replaced them with a high brightness 40 LED strip. I was going to connect this to the brake output on the HexEzcan, but decided to try running it off the rear light supply instead. Somewhat surprisingly, unlike the original bulbs, this does not upset the Canbus, so I don't need to use the HexEzcan for this, so now have one spare output.

As standard the brake light output normally puts out a lower than 12V supply continuously (for the lower brightness rear light function) and ups it to the full 12V to get a brighter output when the brakes are applied. I suspect that if I set the HexEzcan rear light brightness to the same 100% as the brake light output, and turn off brake light flashing, then I will have a spare continuous 12V output which I can use to power some other accessory in future.
 


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