I have a Cobra lightbar and something funny happened to me.
I slid the bar down on the fork tubes to get the lights to line up with the bottom of the main headlight, and all of a sudden they didn't work! I didn't touch any wiring, just loosened the clamp and slid down.
Turns out the bar grounds itself not through a wire but coming in contact with something metal. In my case there was a bar metal piece tucked up there.
I slid the bar back up to be in contact with the metal piece and they worked again.
Maybe what you are dealing with.
Hope this helps.
DarkSider
