maybe it's just the bulb
here's the current status: passenger side headlight has new bulb socket for the non-xenon bulb, new ballast and i just switched out the xenon bulb for another one because we had taken the car to the dealer and they said that it was a defective bulb causing the problems.
the dealer wanted $285 to switch out the xenon bulb so i decided to do it myself, which i did yesterday morning. going to drive it tomorrow to see how the bulb switch works.
if it doesn't work then we're going to get new oem xenon bulbs and try that. the ballast is not that hard to get to, but you'll need to remove the headlight assembly. if you have the time and patience, it isn't that difficult. for us, it turns out that putting in a new $357 ballast might NOT have been necessary.