First post however I have been lurking for some time. Anyhow, my driver's side HID goes on and off quite a bit. Tomorrow I will be switching bulbs as suggested to see if that works. If it is the ballast would that be covered under the certified pre-owned warranty to 100k miles? It has 82k miles on it now. I don't want to waste my time taking it in if it's not covered however I don't really want to remove the bumper to replace either. Thanks!