Brake light functuons only with front brake

[zid]

Hi everyone. I have a serious problem with my Baotian BT50QT-9 (50cc). I have bought it brand new on the ebay and had to mount couple of things myself. It runs ok, but it's rear brake is somehow not connected with battery (as I assume). When I start the bike using electric starter, it will start only if I grip the front brake handle. And when I use the rear brake - the brake light doesn't indicate that I am braking. (though everything works perfectly with front brake). Another thing, I have noticed that when I use front brake it make a silent sond, a tick, and the rear brke doesn't. Also, there is a whire unattached in the rear of my bike, going from a whole where carrier should be attached (though I don't really think that it should be connected with the bulb). I have checked all wires in the front pannel of the bike - everything seems allright. I wasn't been able to check the wires from the brake itself, because I couldn't remove the plastic. Can anyone help me with this problem? Thanks.

[Macrofeet]

the wire is for if you have a rear box there is a light on this see

take the front pannel of and make sure everything is pushed in how it should be

[zid]

Yeah, I thought so (about the wire). About front panel - cheked it couple of days ago. Everything is pushed in ok.

[Botanic]

Check the cable inside the handle for the rear brake. Two screws.
If you have access to a multimeter, you could use it to see if there is electricity in the cables going from the brake to the light. Should be 12 Volts when you brake.