I have an 03 330 with factory xenon lamps. The right one intermittantly turns on slow. Some times it takes 5 mins before it lights off. I swapped bulbs and the symptom stays on the right side.

I understand there is a control module/ballast/ingniter somewhere that fires the lamp. But I can't find any mention of it in the Bentley Service Manual.

Does anyone know where this is?