I have a 2004 RX 330 - I just recently noticed what appears to be condensation inside the passenger side headlight. The headlight works fine, just cannot understand how the moisture got inside what appears to be a sealed unit. I wash this car 50 times a year, never noticed this until this weekend - any ideas what caused and how to fix???

Ensure the headlight capsule is secured, with "O-ring" intact. Perhaps park in the sunlight?