Toyota Repair: Seat Belt, electronic control unit, toyota camry

Question
I have a 87 Toyota Camry.  The driver side seat belt that goes over the chest and travels in the door track when the door closes, or when someone sits in the seat and starts the car, does not move along the door track when the door closes or when the vehicle starts. Any suggestions?
Please help.

Answer
There are many possible problems, this was a somewhat of a bad design as far as I'm concerned, there are switches in the door lock and also limiting switches on both ends of the rails, there is a small electronic control unit and a cable for each side and a motor, there could be a problem with any of these, the most common is that the motor quit, unfortunately Toyota no longer makes parts for this system and you are probably relegated to finding parts at a salvage yard, sorry can't be of more help, maybe you can have the local toyota dealer at least diagnose the problem.