Hi. I posted this info in answer to your reply to my previous post but maybe you missed it. I checked the right hand unit and all but one of the bulb holders look okay. Are the reverse light and brake light so difficult to get out on all 240's? Anyway, the bottom center bulb and socket looked rust stained. In fact, when I tried to remove the bulb from the holder I ended up twisting the glass out of the metal. It's hard to tell but there doesn't seem to be any crud inside the lamp. I can't see a water line when I look straight into the hole. It would seem that water is running over the outside of the unit. But I don't know for sure. I may have to climb inside the trunk as was suggested earlier by someone else.