Weird thing happening with the headlights of my 2005 XJ8L. One headlight on the far (driver's) right hand side.... gets wet after driving! INSIDE! No water leaks, in fact, hoses and radiator just replaced with new ones. Nothing drips in that area when the car is idling. What happens is, after any significant drive, the inside front of that light drips with water! It's clean water. Now, if I take the cap off the back of the light, it doesn't happen. There is nothing "water" in that area! It doesn't matter if the light has been on or off. It appears to be a sealed unit, with an access cap on the back, that is tight. Any suggestions, folks? HAS ANYONE ELSE had this issue?

 

Sounds like your describing condensation to me.

But that isn't a typical issue that i have read or heard of.

A lot i haven't heard or read about though