The front seats on some vehicles are equipped with an automatic seat belt system. The automatic seat belts consist of a driving device assembly, shoulder belt and manual lap belt. The system is designed to provide comfort and safety by automatically fastening and unfastening the shoulder belt as well as automatic retraction of the belts during normal vehicle operation. Sensing devices inside the belt retractor of the shoulder and lap belts are designed to lock the retractors in the event of an abrupt change in vehicle motion.
When either front door is closed and the ignition switch turned to the ON position, the shoulder belt automatically moves to the set (fastened) position around the occupant. When the door is opened, the shoulder belt will automatically move to the set-off (unfastened) position. The shoulder belt on the driver's side will automatically move to the set-off position when the ignition key is removed from the ignition. The belts and door for the driver's and front passenger's seats operate independently of each other.