ELR and ALR seatbelt system

ELR stands for Emergency Locking Retractors. Seat belts are stowed on spring loaded reels with inertia locking. When a passenger moves too quickly or the car decelerates suddenly the seatbelt reel is locked in place by a webbing sensitive lock based on a centrifugal clutch which prevents the reel from unrolling further. This keeps the passenger firmly in place and does not allow the persons body to move forwards.  The seatbelt can be extended further only when it is pulled gradually as is the case when it is pulled for buckling in before driving off. 

Automatic locking retractor (ALR) is another system that locks the spring loaded seatbelt reels at a set position. The system is used for securing child seats, it is also called ‘child restraint mode’. To use the ALR feature the seatbelt has to be extended all the way out to a point when a clicking sound is heard, after which the seatbelt can be allowed to retract up to a desired point at which moment the seatbelt can be held in place and the inertia wheel will be locked by the centrifugal clutch. This ensures that the child seat does not move when the vehicle moves. To cancel the ALR system the seatbelt can be released from the clamp and allow the seatbelt to retract all the way into its retractor.