DISCLAIMER:  This article is for informational purposes only.  Please use at
your own risk!

I can confirm that this tweak works on an '01 TT 225 and '03 A4 Avant 1.8T. Although I have not tested it, this should work on all current Audi cars with OEM self-levelling Xenon lights.

When I recently took delivery of my '03 A4 Avant 1.8T, I noticed that the headlights were aimed too low.  Foreground illumination was excellent, however I was having difficulty picking out signs further down the road. They were certainly not aimed as optimally as the Xenons on my TT (after several trips to the dealer to get it right).

When I parked the A4 alongside the wall of an industrial building at night, a sharp downwards slope was evident.  The lights were aimed approximately 20-30 degrees from horizontal, too low for my taste.

Here is the procedure to adjust the vertical aim of OEM Xenons

1. Park the car on a level surface, 10 to 20 feet from a wall if possible. Connect the VAG-COM as usual, with both ignition and xenons on.

2. Select control module 55 - H. Light Range.  This is somewhat hidden under "Less Common Modules"

3. Take note of the value in the Soft Coding cell.  This is the headlight level as set by the dealer when they performed the PDI.  If you manage to muck things up you can always go back to this default value.

4. Click on "Recode - 07" and you will be able to modify this soft coding value.  A lower value aims the lights higher, and higher value aims the lights lower.  Click on "Do it!" to see the lights move up or down.

5. Don't over do it.  I suggest that you choose a value that still has a gentle downwards slope to avoid blinding other people on the road.  I changed my original value from 00060 to 00020 and it's perfect.

6. Now you need to recalibrate the self-leveling reference point, or else you will throw a code the next time you start the car.

7. To do this,  select "Basic Settings - 04" and scroll up to "Group 001". In a few seconds the first cell will change from "wait" to "set".  Now scroll to "Group 002" and wait until the controller says "Learned"

8. Enjoy your improved visibility!