think about it
the passenger side light works
when you unplug it, and plug in the drivers side, it doesnt work
that means that the issue is in the wiring (or the bulb) of the drivers side light
dont think so?
plug in the passenger side light on the drivers side and see what it does...if it works, you know it is the wiring in the drivers side light
if it doesnt, well, then we got to think a little harder