2015 R1200RT-P - Siren / Horn How To?

[windsailor97]

Hi All,

I recently acquired a 2015 R1200RT-P 45K miles and have been adding a few of the stripped things back on to the bike. I found a rear pod light which adds back additional brake and turn signals (with blue lights disconnected)

I would like some kind of noise maker. The wires are there but just cut back. Everything is still under the rear radio platform. I know the siren is/was a speaker. The BMW siren has a plug with 8 wires from images I have found. The wiring diagram shows a black and white wire going to the siren. If I hook up a siren/speaker to the correct wires, will I get sound? Any thoughts on what I should expect?

Thanks in advance!

 

[pauls1150]

What you can expect is a ticket.
I don't know where you live, but here in CA, it is expressly forbidden in the Vehicle Code for a non-emergency vehicle to have a siren (with very few exceptions).

 

[eplerd]

There is also a powerful amplifier that is required to DRIVE the siren (think home stereo - need an amp/receiver AND the speakers)
I believe the BMW bikes also had a proprietary controller that created the electronic siren "sound" and sent it TO the amp which sent it to the speakers...

Some parts are shown on Bob's BMW's parts fiche
https://www.bobsbmw.com/store/micro...Audio,+Navigation+(65)&MBike=56210&GroupID=65

But as already said, be careful, check local laws on sirens...

 

[windsailor97]

There is also a powerful amplifier that is required to DRIVE the siren (think home stereo - need an amp/receiver AND the speakers)
I believe the BMW bikes also had a proprietary controller that created the electronic siren "sound" and sent it TO the amp which sent it to the speakers...

Some parts are shown on Bob's BMW's parts fiche
https://www.bobsbmw.com/store/micro...Audio,+Navigation+(65)&MBike=56210&GroupID=65

But as already said, be careful, check local laws on sirens...

I don’t want the siren but some sort of honk or beep might be helpful

 

[derache123]

Hey windsailor97, curious if you've had any luck here? I also recently picked up a 2015 RT-P and am looking for the same functionality - the siren speakers are still mounted on the crash bars, but I believe the wiring has been disconnected because neither the horn nor siren buttons work. I don't care for the siren, but would like to restore the air horn since I would like to have a horn to use if I need it. AFAIK, this is the only way to have a working horn on a police bike because they don't come with the regular horn.

 

[pglaves]

So proceed as if you were installing a horn from scratch. You need to get (or find) a relay. You run fused power from the battery to the relay and from the relay to the horn. You run the trigger signal 12v from the switch to the relay and from the relay coil to ground.

You know where the switch is. If you can find the original relay good. If not install a new one. You know where the horn is.

Good luck.

 

[derache123]

So proceed as if you were installing a horn from scratch. You need to get (or find) a relay. You run fused power from the battery to the relay and from the relay to the horn. You run the trigger signal 12v from the switch to the relay and from the relay coil to ground.

You know where the switch is. If you can find the original relay good. If not install a new one. You know where the horn is.

Good luck.

Would it be illegal to simply restore the original police-type air horn functionality? Given that the speakers themselves and the wiring are still present on the bike (just disconnected), this would seem way simpler than installing a normal horn from scratch. And as far as I can tell, there doesn't seem to be anything in the California Vehicle Code that specifically prohibits this.

 

[pauls1150]

Air horns are permitted with the caveat that "no horn shall emit an unreasonably loud or harsh sound."
(Division 12, Article 1, Section 27000a)
Any horn that uses a compressor is an air horn, so yes, they "can" be legal.

 

[derache123]

Air horns are permitted with the caveat that "no horn shall emit an unreasonably loud or harsh sound."
(Division 12, Article 1, Section 27000a)
Any horn that uses a compressor is an air horn, so yes, they "can" be legal.

That was my interpretation as well. I don't think the police air horn would be any louder or harsher than some of the aftermarket blasters I hear on pickup trucks these days so I guess I shouldn't be too worried. Being a motorcycle rider, I wouldn't mind erring on the side of loud/harsh anyway, if it would be better at grabbing drivers' attention.

 

[milosovichy]

I have a 2015 RTP which had the sirens and lights removed. However, I sourced a new horn (denali mini-soundbomb in this case), which installed in the civilian location (in front of the head stock) and used an adapter to adapter to the 3 pin BMW cable to the 2 spade connectors on the horn (denali too). Took it to my local BMW mottorad shop, who were able to reprogram the horn to work when activated with the normal horn button (this last step was necessary as the RTP are preprogrammed for siren only). Wasn't confident this would work and it has worked magnificently.

Let me know if you have any questions.

 

[20774]

Welcome to the forum, and thanks for the "hack" on getting this done!

 

[kbasa]

What you can expect is a ticket.
I don't know where you live, but here in CA, it is expressly forbidden in the Vehicle Code for a non-emergency vehicle to have a siren (with very few exceptions).

Any appearance of insignias similar to law enforcement is also illegal. Flashing lights may be restricted in certain jurisdictions including disallowing specific colors to be used by civilians. Be super duper careful about trying to build a replica LEO RT so you don't wind up dealing with an Impersonating an Officer charge because of your bike.

 

[windsailor97]

Can anyone tell me why the siren speaker has all these wires?

 

[windsailor97]

I found some wiring diagrams. I am not 100% sure what the acronyms mean. LIN must be a LIN bus reference, PPT push to talk, NF and Mute are PA related. Not sure which is the air horn or if connecting a basic two wire speaker is even possible.

https://aws-p-app1.bmwcenternet.com/bmw_mc_police/Media/Media.aspx?uid_media=360&uid_media_type=2