I own a 2006 B6 3.2V6. I am getting an intermittent warning that the passenger door is open as I am driving. Generally, the "door open" alarm will sound and the interior lights will come on for a second or two. This may happen several times in the space of a couple of minutes, or it may not happen at all.... Also, my alarm intermittently sounds when the car is locked, for no apparent reason.. I am guessing the two issues are linked, ie. vehicle locked, vehicle senses passenger door opening, alarm sounds.. does anyone know how the vehicle detects a door opening? I've looked for a physical switch unit but cannot find one.