This is a relatively minor issue but though smoeone might have some insight. I have a 1990 300sl. On startup, the charging light illuminates and stays lit until I give it a little rev. Once I've been driving it, if I come to an idle the seatbelt light will flash if I have a few accessories turned on. If I turn the heat on full blast, put the seat heaters on etc., the seatbelt lamp lights and stays lit. No problems when I have my foot on the gas... Any thoughts?