Pull EVERYTHING. All of it. Plug in the 12 volts plus and minus, make sure it's the right polarity (red = +
), make sure the battery you use is fully charged, and see if you get the light. If you still have a 5v low, the RC is toast...otherwise it's somewhere in something you wired, probably in the camera. I take it you're at the Great Lakes Regional? If so, if you can't figure it out and I'm not too frantic, you can swing by 68's pit and I can try my best to fix it.
Good luck,
JBotAlan (Jake)