Now that it's getting darker when I head off to work in the morning, I have to use the headlights. I noticed (I think) that when I first switch on the lights, they appear to brighten up over a short period of time, maybe a few seconds or so. My 8 came with the Sport package which I believe includes Xenon lights along with Halogens. Does one or the other get brighter as they warm up?

1.3L

 

xenon head lights are the ones that need about a second or two to get brighter

 

You're right. It takes about 5 seconds for the xenon gas to get going all the way. It's the same with flourescents but it doesn't take as long. You'll also notice it with Metal Hyllaides, High Pressure Sodiums, and Mercury Vapors as well.

 

http://www.howstuffworks.com/question387.htm

^ What 93rd said

 

I wish they stayed the intial blue color.....