My driver side low headlamp, which is a HID lamp, cycles on and off, mostly off now. I first tried replacing the bulb (carefully) but same result. There is also an igniter and a ballast. I know the igniter is getting 12 volts. How can I tell which of the remaining two parts are faulty? These are expensive parts, any suggestions where I can get a replacement part (exact fit please)?

 

the control unit and igniter are 1 unit we are seening a lot of them now i personally did 3 cars this month. was cool though like a light show with them cycling on and off so fast waiting for something to fry.
hold on to your check book they are not giving them away.
about 600.00