In Reply to: Xenon Light "Check Low Beam light" posted by Aaron Liu on July 03, 2000 at 11:17:06:
If these are the original factory BMW HID lights then my guess is that one of them is starting to fail. It will probably be the ballast/controller that is the fault, and my bet is the left (driver's) side unit due to the extra heat in that area from the oil filter.
When you turn on your headlights watch for an extra flickering as it tries to fire up.
Report this as soon as possible - it is a recognised issue with the first version of the HID ballast units in the E39 (the larger cube shaped metal box units, as opposed to the flatter units used now.