My friend has a 02 or 03 mustang and her headlights are messed up and the solution might work for all headlights for any cars but i thought i would specify just in case. The driver side light looks like it is on high beam while the one on the passanger side is so dim that you can hardly see it... they are aftermarket projectors and i do remember seeing them having water residue in them frm time to time... Anyone know whats wrong or how to fix it? thanks!

 

Pull the bulbs out, swap the them from one side to the other. If the problem has now switched sides, get new bulbs. If the problem stays on the same sides then it's an electrical problem.

 

thanks man. I'll give it a shot.