Vehicle Sensitive; Automatic Locking Mode - Ford Thunderbird Owner's Manual

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/jerking on the belt.

Automatic locking mode

In this operating mode, the shoulder belt
retractor will be automatically locked and remain
locked when the combination lap/shoulder
safety belt is buckled, and does not allow the
occupant freedom of movement. This mode
provides the following:
A tight lap/shoulder belt fit on the occupant.
Child seat or infant carrier installation
restraint.
Rear-facing child seats or infant carriers
should never be placed in the front seats.
This mode must be used when installing a child
safety seat on the front passenger seat and rear
outboard seats where dual locking retractors are
provided.
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