On Fri, 7 Oct 2005, Arif Khokar
H'm. It could be dead, but so could be the ballast. Have you swapped bulbs side for side to see if the failure moves to the other side?
Please define "a lot". Is there actual liquid water sloshing around in the headlamp? Or are you just seeing mist that doesn't go away (because the lamp isn't lighting, hence no heat to drive-off the moisture)?
This is on...erm...*which* Audi that has an H4 high beam bulb? Think you mean H7.
If that happened, you will know it as soon as you will remove the bulb from the lamp -- it will have physically shattered.
Rated life is 1500 hours (B3), 3000 hours (Tc).
B3 is the hour figure at which 3 percent of the bulbs have failed on the test rack. Tc is the hour figure at which 63.2 percent of the bulbs have failed on the test rack. So, while these two figures are a good predictor of the early-failure rate and the longevity of a given bulb type, they are not a perfect predictor of the lifespan of any individual sample.
I'm sure you can probably figure out where to get a replacement bulb of standard or nonstandard specification. ;-) Do note that you may be unhappy with the colour mismatch that often results from replacing *one* of a pair of HID burners.
-DS
