Topic: cb550 k3

[busa]

Hi guys
I need help  please.   fitting wiring harness to bike.  connecting all multiplugs  etc.   on the left hand switch gear  horn button.  the light green wire from switch to plug is there,  and also in the female multiplug that it plugs into.  the problem I have is that I can not find the feed for the horn it self.  (there are no wires on the horn)   am I right in thinking there should be a black wire  and a light green one coming from the horn. if so to where!!!!!!!!!!

the bike is a uk bike 77/78 cb550 four k3.    but using the full electrics  from  same bike  but Canadian model (everything electrical came from Canada,  including switchgears.

many thanks

[busa]

have found the correct wires.  but horn button not working Have put a test light on the black  it has power
but nothing on the light green.   and nothing from button.     think the horn itself is also  faulty.  using jumper straight from batter to horn.   nothing.  !!!!!!!!!!!!

any ideas?  please

[Frostyboy]

Put a test light in series between the black & light green down near the horn.
The light should glow when you push the button. The green goes to ground when the button is pressed.
Sounds like you need another horn if no sound when across battery.

[busa]

Hi mate thanks for that.  tried that and nothing, from button.  also did continuity test on button  nothing.   
but then  me thick or what  checked the fuses    the fuses for tail and head  has blown.   but don't think  that would stop a continuity check. (I am not 100% with elecs)

the frame is grounded  even though its a fresh paint frame  had to clean off new paint  nice and shinney  to get a good earth

[Bankerdanny]

The blown fuses would not matter when checking continuity across a switch.

Sounds like you need to open up the control and check where the wires are soldered to the switch contacts. If both seem solid then check continuity from the input wire to the contact on the switch, then again from the contact out to the horn. Since those wires are hidden inside a sheath you could have a broken wire and not know it.

This has happened to me on a couple of bikes.