Can anyone explain this seat belt warning light schematic to me?

86 - 12v from the buzzer.
15 - 12v from the ignition switch.
G - Ground through the seat belt receptacle switches. (Is your seat belt latched?)
50a - ????

I have 1 car that doesn't light up at all and another that flashes. I thought the seat belt light was not supposed to flash and didn't have anything to do with the e-brake switch.

Thanks.

Mark, here are the 3 pages that address it in the 74 Service & Training Manual, don't know if they help you:

Thanks Jeff. That stuff is the seat belt interlock system. This diagram I posted is actually a little circuit board inside the red Seat Belt light on the dash. I think I have it figured out now. I don't understand what the resistors are doing, but I understand the broad picture.

Oh well.