I pulled the dome light and found that there was no power coming up there from the driver's door. So I chased down the seatbelt warning buzzer and pulled it out. I took it apart and there was two places where you could see the solder wasn't making good contact. I tested the relay's circuit with my continuity tester and found it was not complete. Got out a soldering iron and heated up the two open parts, and it works as good as new. It would be tough thing to solve without help from others on this site.
P.S. I think older MBs should have a soldering iron in the toolkit in the trunk.