I get the same thing with Auto lights. I've noticed that the lights will switch on as they should when light levels get low enough, but they will also come on in bright sunshine. I thought this may be a safety thing for drivers coming in the opposite direction and have the sun in their eyes that they will more easily see you coming toward them if your main lights are on. Then again I may be talking complete Bo@~#ks.
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BMW 640i Titanium Silver, Vermillion Red Nappa Leather, 19" V-spoke style 366 alloy wheels, Comfort seats. Front Contrast stitching, DAB digital radio, Instrument panel with leather finish