Steve1965

I've been having trouble keeping lights working on my 2003 A4 Avant wagon. Every 3-6 months a head light or tail light burns out. I currently have an intermittent problem with a head light. Sometimes the dashboard indicates the light is dimmed, then it comes back on. Any help would be greatly appreciated.

diagnosticator1

If the intermittent condition exists, then there is a loose or corroded/dirty electrical connection somewhere. Most likely at the headlight chassis harness connector, or the lamp connector inside the headlight housing.
The taillight bulb sockets are known trouble, and are also loose connections to the bulb when installed in the socket. Carefully bend the bulb contacts inside the lamp socket up a little, to press on the bulb with more pressure when the bulb is inserted into the socket. Also use a thin film on Vaseline, or dielectric grease on the bulb bases to prevent contact corrosion.