Signal fuse blows

[indiaguy]

Hi, long time since I posted here. Been riding my 81 bobber for ages with no problems.
My buddy's 78 special(my old bike) suddenly started blowing the signal fuse.
Upon inspection, it going straight to ground.
I've disconnected everything and the only thing I disconnect that makes a difference is the little black box at the back of the battery.
The bike is still points.
It's got "Koito 12v" written on it, I can't for the life of me remember what it for?
Is it part of the emergency lighting system?
Is it prone to failure and can it be junked?
Any credible suggestions would be a great help.

 

[retiredgentleman]

Hi, long time since I posted here. Been riding my 81 bobber for ages with no problems.
My buddy's 78 special(my old bike) suddenly started blowing the signal fuse.
Upon inspection, it going straight to ground.
I've disconnected everything and the only thing I disconnect that makes a difference is the little black box at the back of the battery.
The bike is still points.
It's got "Koito 12v" written on it, I can't for the life of me remember what it for?
Is it part of the emergency lighting system?
Is it prone to failure and can it be junked?
Any credible suggestions would be a great help.

Its the "Light Checker". You can just unplug it, and not use it, but you will have to join the blue wire to the blue/yellow wire (so that the tail light works) at the Light Checker plug.

 

[indiaguy]

Are you talking about the "emergency lighting device" that's also behind the battery but it's clearly written on it.
I'm referring to the black rubber covered block that's almost underneath the battery, hidden away. I'll jump the wires anyway and see.

 

[Grinder]

The item mounted to the bottom of the battery box is the rectifier for the charging system. It would have the three white wires from the stator going into it.

 

[retiredgentleman]

Are you talking about the "emergency lighting device" that's also behind the battery but it's clearly written on it.
I'm referring to the black rubber covered block that's almost underneath the battery, hidden away. I'll jump the wires anyway and see.

You said the "back" of the battery.