My wife just came back from about a 3 hour trip in her 3.0. The car won't stop beeping when a door is open. I checked the headlights and every other feature I could think of and it just keeps beeping. When I shut the door or start the engine, it stops. I did a quick check thru the owner's manual and found nothing. Then it dawned on me - ask the experts! Any suggestions would be great appreciated.