Problems with door locks are a sign of a faulty actuator. Bad actuators can fail, resulting in the driver-side door lock failing (more often than the other door locks). If this occurs, the actuator can be defective. If none of the locks work, then the fuse box may be defective. In some cases, the issue is caused by a blown fuse. In general, blown central locking fuses, broken door lock solenoids, and damaged electrical wires can all potentially cause door locks to not work properly.