Black is the ground, should slide on small thread stud. The white are the tails. Large red battery feed. Sounds like fuse, or the light switch in your hand. Should have power to white wire when switch is pulled. Do the dash light work? Should come on with tail lights. The grounding on Jeeps is not the best. There's a good post in the forum on grounding. Easy to do and solves alot of problems. Good Luck!
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