Symptoms: After driving a random amount of time the Citroen C6 headlight started flashing/flickering a few times and after a few minutes one of the lamps turned off. The telltale light on the dashboard for the lights was blinking. For a while it was the driver’s side lamp, and later on switched to the other side. After turning the headlights off and on again, the lamp was working for an unknow amount of time, after which the history repeated itself.
Solution that worked for us: changing the bixenon bulbs.
We initially thought that the ballast is gone on the car, but later turned out this was my mistake confusing Xavier´s Diagbox reading with Maudette´s issues. Xavier indeed had a B1122 Ballast error. This confusion sent us a bit on the wrong direction, but luckily at one of the C6 meeting, talking with one of the participants who is very well versed in all C6 issues, he suggested us to start with the bulb, because that could be it. The consensus is generally that aged xenon bulbs turn pink, and ours were not showing any sight of that.
Anyway, our mechanics were a bit puzzled why we want to change a bulb that “works perfectly” (they don´t know the works randomly for 30 minutes or 2 hours even, when the issue shows), but slowly they are getting used with our crazy ways of doing things.
After the lightbulb change we drove about 830km with light and not a single flicker happened, so we dive in and drove on our way back during the night and also no issues were showing. After close to 1700km, I can safely say our flickering, turning off light issue is now sorted. Yay!