Audi Repair: lights!!!!!, xenon bulbs, xenon headlights

Question
I have a 2004 audi 4 quattro.   One day when I started the car,the error message said that the left dipped headlight and right rear light were out.  Next day, only the headlight.  Then right and headlight. Then only the headlight.   The days have been damp and rainy.

WHat's going on?  Isn't the headlight expensive to replace.  I don't want to do that if it really doesn;t need it and will magically return like the back light

Thanks  

Answer
hello
Looks like nee may need some bulbs, Rear bulb - just see which one it is and replace it. Same deal with the front , If you have xenon headlights  , swap the bulbs and see if cluster display the other side. Xenon bulbs are not cheap, so I always swap them to see if it's the bulb itself. If swap does not help - you have bad module ( some people call it ballast or igniter)
good luck          Greg