emax-110s scooter rear break light

i have a probblem and carn't seem to find the cause would it be easy to
make a 12v bypass from one on the 12v batteries ? it has 4 12v batteries
break switches are working fine how would i go about wiring the switches to the rear light
so the rear break light works as the swiches are getting a 12v suppliy to them but somehow its
getting lost throught the electrics and is showing from the three wires to the rear light
one is green/yellow .( middle wire is green ) and the third wire is brown ......