I recently bought a 2003 built RV-9A. Very nicely built but with a few squawks due to age. The left Nav light works fine and shows just under 12 volts while the right one shows only about 2.5 volts. Both lights are in the fiberglas wing tips and seem to use the ground from the strobes which is wrapped around one of the screws holding the light on as the return. The Nav lights only have a hot lead and the ground is thru the body. The strobes work fine. Why would one work with this system and not the other. I haven't tried running a separate ground lead from the Nav/Strobe fixture to the plane body yet.