The Honda brake light wire is Green/Yellow. The Honda ground wire is Green.
When you apply the brakes, the GS-100A flashes the brake light – 4 quick flashes, 4 slow flashes – then the regular brake light operates normally.
To install this you need to remove the seat. The brake light wire is Green/Yellow. You have to cut that wire and connect to the red wires on the GS-100A. Wire the two black wires on the GS-100A together and connect to ground. See wiring diagram above.
Rebel500 