First nothing works. Relay and fuse are good. I swapped a known good relay "K" for old and no difference. I take back tailgate panel off (740 wagon) and reach in with pliers and yank real hard on unlocking rod while my wife turns the key on and off in driver's door. Back panel locking actuator suddenly breaks free and now works fine. Put everything together and tested doors using driver's door lock. Tailgate still works fine but none of the other doors lock or unlock using key or pushing down plunger. This all started when I oiled the tailgate lock cylinder a couple of weeks ago. Don't ask me how that would be related to this. Before oilingall the central locking actuators worked great on each door.