Horn Technical Question

[Skywagon]

When BMW went to the single horn that goes meep meep, it was a serious departure from the dual horns on my old 1150RT.  A couple of years ago I bought a set of dual horns, made a bracket, installed them, and found out they wouldn't work.  The circuit would shut down when you hit the button.  I now have a dual wiring harness and relay that should work.  I'm going to try again this weekend to get the 1150 dual horns going with this new harness and relay.

 

Here is my question.  Is there something that could be done (I'll use layman terms describing this as will most likely call something the wrong thing) to the electronics via a GS911, something in the circuit, or the dealer to allow the original circuit to accept the load of two horns?  Rinkydink gave me a horn about 6 months ago that was a good bit louder, but I want to try and get my 1150Dual horns High and Low working.

 

[RadioFlyer]

No, it is not possible for a GS-911 or the Motoscan app to change the overcurrent threshold of the ZFE.

 

I doubt that a dealer can do it either as BMW would not likely have permitted a higher current given the small gauge of the wiring.

[LAF]

I would just do a relay and fuse to battery and call it a day.

 

It for sure is a wire thing as they are thin gauge to say the least.

[dirtrider]

3 hours ago, Skywagon said:

When BMW went to the single horn that goes meep meep, it was a serious departure from the dual horns on my old 1150RT.  A couple of years ago I bought a set of dual horns, made a bracket, installed them, and found out they wouldn't work.  The circuit would shut down when you hit the button.  I now have a dual wiring harness and relay that should work.  I'm going to try again this weekend to get the 1150 dual horns going with this new harness and relay.

 

Here is my question.  Is there something that could be done (I'll use layman terms describing this as will most likely call something the wrong thing) to the electronics via a GS911, something in the circuit, or the dealer to allow the original circuit to accept the load of two horns?  Rinkydink gave me a horn about 6 months ago that was a good bit louder, but I want to try and get my 1150Dual horns High and Low working.

 

Evening David

 

Not that I know of as the internal driver inside the ZFE is pretty limited. 

 

If you use a relay that is controlled by your present horn button (ZFE controlled) you should probably use a relay that is protected from back EMF.  Those have a clipping resistor across the pull-in coil terminals to prevent a  high voltage spike back into the ZFE.  

 

[Rougarou]

I run two Stebels on the RT.  I "tapped" into the factory horn wire, ran that to a relay, then the main power directly to the battery.  Don't think that helps you, but it's an option to run.

[Skywagon]

Thanks all...I didn't think there would be a programmable answer but never hurts to ask.

 

DR..I made up a wiring harness with the diagram you sent me a while back.  I'm not sure if the relay has the resistor or not.  I'll check.  It was a spare I had from my R100RT a few decades ago.

 

Do you have a source for that relay?

 

Just looked...the relay I have doesnt show the markings you have...so guess I need one.

[dirtrider]

13 hours ago, Skywagon said:

Thanks all...I didn't think there would be a programmable answer but never hurts to ask.

 

DR..I made up a wiring harness with the diagram you sent me a while back.  I'm not sure if the relay has the resistor or not.  I'll check.  It was a spare I had from my R100RT a few decades ago.

 

Do you have a source for that relay?

 

Just looked...the relay I have doesnt show the markings you have...so guess I need one.

Morning David

 

A properly resisted relay is always the safe way to add extra relay controlled circuits. Look closely at your relay. If it is OEM from a BMW 1100 then most 1100/1150 OEM Motronic controlled relays were resisted across the pull-in coil to prevent back EMF into the switches or control circuits.