Small electrical nightmare
 

My 86 420 SEL's radio apparently has a mind of its own and works only when the door is open. The under door light on the drivers side does not come on except when the passenger side door is opened. All other under door lights work fine. The overhead console made a funny throbbing noise when the switch was placed in the normal operating position(last towards the windshield) Has anyone seen this problem before? Thanks

Sounds like the seat diode in the fuse box is bad.
Also most likely an issue with the warning buzzer.