Hatchback/liftgate Lock problems of the 1996 Nissan Quest

All doors will lock under 3 scenarios: 1) doors will relock immediately following, unlocking the doors. 2) doors will lock after closing driver door. 3) doors may lock without any action taking place. Could be locked out of vehicle if doors lock when closing door, with keys in the vehicle. Dealership replaced door lock actuator in 1998, problem started reoccuring in 2002 and continues to occur intermittently.