Well, the red is the hot lead from the battery, the black is the power circuit to the rest of the bike and the brown and brown/white wires complete the tail light circuit. You gave something in the tail light circuit a hefty jolt. From what I can tell, the brown wire goes straight to the tail light and when you put the switch in the "Park" position, those two get connected anyway, so the red wire probably hit the brown/white stripe wire. This wire goes back to the instrument lights and up to the light switch in the control pod on the handlebars, where it gets juice from the black wire. (also powering the headlight hi/lo beam switch). Hmmm... I might have a better diagram. Let me look. If I figure it out, I'll post something. Sorry for the rambling, hope it was of at least a tiny bit of help...
