OEM HID Question
 

So my car came standard with the oem HIDs. I sold my custom headlights that were originally oe hid, the person gave me cash plus his headlights. But it turns out he did not have the factory hid setup. To me this is okay because I'm tearing the projectors etc all apart, all I needed was the housing.

My question is: Where are the oem hid ballasts located? Are they part of the car or in the hid headlights? I noticed my old hid lights had one more plug than these, which I read is the auto leveling unit (3 prong triangle black connector).
Is the 2 wire small connector right next to that triangular plug standard 12v or has it already been through a ballast?
The answer to this will determine how I make my next lights. If the power is already converted by the time it reaches the lights I can just hook it directly up to new HID projectors (I believe), if not I'll need aftermarket HID ballast.
Thanks in advance.

The ballast units are fixed to the underside of the headlamp assemblies

perfect. So I can just wire up the new lights with aftermarket ballasts.
I appreciate the clarification.