BMW 328i Convertible ambient light sensor?

Perhaps you are confusing ambiance lighting (usually used in nice restaurants for "mood" lighting) with ambient light (which is what ever light is present from the environment. Or perhaps you really are referring to ambiance lighting in the real sense of the word. There is no provision for ambiance lighting in a BMW for most everything is there for functional lighting and not for mood setting.But there is an ambient light sensor built-in to the car which tells the headlights to turn on when it becomes sufficiently dark. To turn on the automatic headlights based on ambient light conditions, the light switch must be turned counterclockwise to the leftmost (position A, as in automatic, and not accessory). There is also the interior light switch above the rearview mirror, which works with the door microswitches when the door is opened. The remote also triggers the interior lights to come on. The car/key memory which is programmed into the general/basic module also has something to say about which lights come on or not.