Topic: 400F UK left switch into US harness

[gregk]

I'm trying to get a UK version of the horn/headlight control to work on a US bike.

I've been able to sort out the double filiment bulb issue on the front end and now signals, running light, brake light, headlight (high and low) all work. Even the headlight pass thing works. The horn however does not.  The wiring diagrams for the UK and US are different for the horn.  The horn does work when I hook it up directly to a battery and the switch is "new off e-bay".  It looks like the UK version grounds a black wire to the frame?  I thought the black is hot?  The light green goes to the horn.
The US version must ground into the wiring loom? 
Anyone have any answers?

Greg

[bryanj]

Check wether the switch grounds the horn wire or connects it to a power wire as this will vary your wiring----both were used at different times

[GroovieGhoulie]

I dealt with this EXACT problem when I wired my UK switch.  The UK wiring grounds to the frame, the US to the harness.

Go to the hardware store and buy a female bullet connector with the flat ring on the end.  Plug the end of the black wire into it, then unscrew one of the screws for the horn mount, stick the connector between the frame and mount, then tighten  it down, up against the frame. 

Voila!  Horn is grounded and works.

[SteveD CB500F]

Voila!  Horn is grounded and works.

That'll be a French Horn then GG?

[GroovieGhoulie]

Voila!  Horn is grounded and works.

That'll be a French Horn then GG?

I was wondering why instead of beeping when I pressed the button, it played th first few bars of "La Marseillaise".

 

[gregk]

GG
 If I understand this grounding thru the frame, then there is one terminal empty on the horn?  You say to run the black wire from the switch to the ground where the horn mounts to the bike.   The light green then  goes to either terminal?

Greg

[bryanj]

NO, one version has one horn terminal fed with power and the other grounded by the switch
2nd has one horn terminal grounded and the other fed power from the switch

[GroovieGhoulie]

According to the diagram, the LG out of the horn switch plugs into a LG 2-into-1 plug on the harness.  The LG out of the horn itself plugs into the other female side.  The black wire coming out of the horn itself is grounded to the frame.

[gregk]

GG

I grounded the horn to the frame like you said and took the LG wire to to the other terminal and everything works

Thanks

Greg