Is the brighter mode driver's side tail light actually the rear fog light? I have a dash light indicating the rear fog light is out. I wasn't even aware that my car had the rear fog light. Our 740 had a dash mounted switch to turn the rear fog lights on, however, our 850 has no such switch...or does it? I have swapped out the brighter light on the driver's side with a good bulb and the light still comes on, and the light still shines brighter than the passenger side. Does this require a special bulb? I know the two lamps for the license plate are also out...does this have anything to do with this rear fog light set up? Thanks in advance.___mark.