So I noticed my passenger side headlight went out and also some water got in the headlight. So to see if the bulb was the problem I switched the bulbs around (passenger bulb, to the drive side) & the bulb works on the driver side but not the passenger side. The high beam on that side is also out. So any ideas on what it could be?

 

Well, if there was water in the light housing (no fender liners?), maybe you have a blown ballast (if HID), a blown fuse, or just enough corrosion to cause a problem. Nothing else anyone can do from here, you're going to need to do the rest yourself. This is basic troubleshooting.

 

Sounds like you ruled out the bulb by swapping it with the D/S. Try doing the same with the ballast as the next step.

But, since you mentioned the high beam is out also (I'm assuming it's 03-05 HID and the high beam is the separate H7 bulb as opposed to the 06+ bi-xenon), I agree with dcains it sounds like a fuse/connector/corrosion problem from water damage. Check the grounds and clean them up with some contact cleaner.

The year and model (i.e., 2003 base) would be helpful.