I see that this thread is a bit old, but to me, it's still relevant. I bought a 2011 Regal 2 years ago as my first car and I've loved it. Haven't had any issues until this past winter. My current issue is my headlights or (one) headlight in this case. My left front headlight is out, unfortunately, it's the HID light. I bought a replacement bulb and go figure, it didn't work. I ended up taking it to the dealership to have it looked at and they told me I need a new ballast. They said it was a $260+ part. didn't have that kind of money at the time so i've just been putting it off.
Where can I find one cheaper and what exactly am I looking for? They didn't give me a part number and there are tons of things that pop up online, but they all seem very different. Any help would be greatly appreciated.