BMW Repair: FLashing ZENON HEADLIGHTS, xenon lamps, xenon headlights

Question
Hello  Mr Slater
I got a 99 e46 with flashing  xenon headlights, and it has became a problem. Earlier it just flashed occasionally, but now its almost all the time. Does not matter if I drive or the car is parked.
I have checked for bad connections,even in the fuse box.
And when I turn on the highbeam it is all the time, but only the xenon lamps flashes.
Both can flash at the same time or they do it one at the time. The lamps can also go out one at the time, but it has also happened that both have gone out when I'm driving ( no fun ).When this happens, I have to turn off the headlight switch maybe a couple of times , to get the xenon lamps back on.
I think I can see that the park bulbs are pulsing a little bit, also the same for the dome lamp.
Any ideas? My BMW dealer can not help me.
Look forward to your answer.
Best regards
Paul Nilsen
NORWAY


Answer
Paul, I usually see faulty Xenon control modules (mounted on the headlight) or faulty ignitor assemblies located in the headlight itself. Try unplugging one of the headlight and drive it. If the other light works normally then the unplugged module is most likely at fault. If not try the other module and reconnect the first. If you find that one side is at fault then swap the suspect module to the other headlight and vise/versa. See if the symptoms transfer.
-Evan