which fuse goes to the tail lights?
Try this link, should be exactly what you're looking for. http://www.jeepforum.com/forum/f13/zj-fuse-panel-diagram-1993-1995-a-611159/
Not very helpfull. The tail lights are not mentioned anywhere, so they are incorperated with another fuse. Most likely the parking lights. However the license plate light should also be on this, so if it works, you have another problem. The contacts are probably dirty. try changing both bulbs first.
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