How do I troubleshoot a solenoid??

[louky]

I just picked up a 50cc taotao with a no start condition. The battery is OK and charged but it won't start with the key. I can start it and run it by jumping the two big terminals on the solenoid. What I don't know how to do is to electrically bring the solenoid in to prove it is OK. There are two small wires going into the solenoid, yellow/green and yellow/red. How do I put 12 volts on these wires to jump the solenoid?

Also, I found a plug not plugged in but can't find the mate to it. The wires on this plug are solid green, and black/white. Any ideas what this might be? The location is around the spark plug. I haven't taken all the plastic off yet.

I know I need to verify that the starter button itself is working, the shut off switch, and the brake switch. I don't think this one has a kickstand switch. Is there anywhere else at for a no start?

Thanks