It sounds like the alternator. To be sure, use a voltmeter across the battery while the car is running. The reading should be 14.4 volts, which means the alternator is working properly, and the battery is not holding the charge, in which case the battery should be replaced. If the reading remains 12volts or lower while the car is running, it's the alternator.
As for the automatic seatbelt, it sounds like the belt inside the retractor may have broken. The switch that indicates an open door also feeds the automatic seatbelt unit. I'd live with the noise rather than disable the unit.
Wednesday, January 18th, 2006 AT 11:25 PM