Last day, when testing a repaint, I saw something flickering, like a flashing light (view outside, MAN LCC, MAN LC is ok). I saw that a inner light is on (even if all lightswitches are off).
Another thing, which was allready explaned by some in an older version of FB, probably a forgotten bug, when doing a reverse maneuver, some inner lights switch on (see 2 pictures with Flixbus livery : first, (gearbox is set on D) , second (Gearbox is set on R).
Hope this can help you.