Repeated issues with faulty door lock actuators on lexus ct and toyota prius models, resulting in unlocked doors at times when locked would be desired. in this particular lexus ct, the first door lock actuator stopped working at 36,000 miles exactly; driver's door. the second stopped working at 39,000 miles; driver-side rear door. the third stopped working at 39,500 miles; passenger- side rear door. problems occur as car is stationary but being put into gear; then persist as driver is in transit. (for instance, if the door doesn't lock, it remains unlocked as driver is at stop light.) same problems on a 2010 model year toyota prius, which is built on same or similar platform as lexus ct. replaced six door-lock actuators in 5 years on this 4-door car.