I was in an accident a couple weeks back with a deer. We have gotten my driver's side lights replaced. It already has HID in the car, but my lights were blue before the accident. Now I have one that is the OEM white and the other that is being explained as an aftermarket blue. So right now we are trying to figure out how to get my headlights looking the same and insurance is becoming more of a fight now. But what I want to know, if I get a kit for my car to change the color, is that possible to do with an OEM HID system and if so, how difficult is this to do? I REALLY like the blue light I had, but ultimately I just want to get my CTS back to looking good. Right now two different headlights looks just awful.
Are the lights you have in there OEM Cadillac? This issue could be the bulb or ballast which can be determined by switching your bulbs from side to side. A new kit would potentially solve this as all components would be replaced. You can then also choose any bulb colour you want. The install will depend on if this car is setup for OEM HIDs or halogens originally.
Let me know on the above questions and we can go from there.