Hey I have a question about replacing headlights on my 2001 Audi A4 Quattro. My passenger side headlight is currently not working. When I turn on the lights, it kinda blinks three times and doesn't turn on..... I am confused as to what parts I need to get. An auto parts store said the part is $300 and includes the ballast. Alternatively I found a bulb online for about $100 but it didn't say anything about the ballast. I don't have any experience so far with these high intensity light systems so if someone could give me a clue it would be much appreciated, thanks!