Failure xenon light

Hello, maybe one of you can help. For some time, a xenlight has been out during the journey with light, the on-board computer then shows me that. When I turn the light on and off, both lamps work again. But this does not seem to me to be due to the xenon lamp, but to something else. If the xenon lamp is defective, then it is really defective. Are there any fuses and capacitors here that may be defective? Furthermore, a cable to the brake lining wear indicator probably has a cable break. Left or right, I haven't figured that out yet. Every time I hit the left side, the surface display goes on in the on-board computer. Audi has a repair kit here, because this has happened several times. Any of you have any experience with this. Is it hard to do this yourself????