Dual Locking Mode Retractors Operate In Two Ways - Ford Ranger Owner's Manual

Unfastening the outboard lap/shoulder belts
While the belt retracts, guide the tongue to its original position
to prevent it from striking you or the vehicle.
Safety Belts for Front Outboard Passenger and Rear
Outboard Seating Positions
Your vehicle is equipped with a dual locking mode retractor on
the shoulder belt portion of the combination lap/shoulder safety
belt for the front seat outboard passenger and rear outboard
passengers.

Dual locking mode retractors operate in two ways:

Vehicle sensitive (emergency) locking mode
In this operating mode, the shoulder belt retractor will allow the
occupant freedom of movement, locking tight only on hard
braking, hard cornering or impacts of approximately 5 mph
(8 km/h) or more. The retractor can also be made to lock by
pulling the belt out quickly.
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