Litronic occasionally turns itself off?

[fridsten]

I have factory Litronic headlights on my base -99. Recently I've discovered that the left light turns itself off from time to time. There's no obvious pattern to it. When I turn the lights off and on again, it works again. The difficult thing is to know when it goes dark.

I'm guessing it's either the Control Unit or the Ignition Control Unit for the headlight. Since it only occurs on the left headlight, I don't think it's related to the switch.

In Sweden it's mandatory to have low beams (or DRL) turned on during the day as well, so I need it to work.

Any thoughts?

Forgot to mention that I've replaced the bulb. That's not the problem.