FORD 2004 F-150 v.4 - Manual (Page 111)

The driver and front outboard passenger safety belt pretensioners are
designed to activate only during certain frontal or near-frontal collisions
with sufficient longitudinal deceleration. A safety belt buckle
pretensioner is a device which tightens the webbing of the lap and
shoulder belts during some collisions in such a way that they fit more
snugly against the body.
The driver and front outboard passenger safety belt system (including
retractors, buckles and height adjusters) must be replaced if the vehicle
is involved in a collision that results in the activation of the safety belt
pretensioners. Refer to the Safety belt maintenance section in this
chapter.
Failure to replace the safety belt assembly under the above
conditions could result in severe personal injuries in the event of
a collision.
Safety belt usage sensors
The driver and front outboard passenger safety belt buckles are
equipped with sensors that detect if the safety belts are fastened. The
sensors provide information to the Personal Safety System which can
then adapt the air bag deployment or safety belt pretensioner activation
based upon safety belt usage.
The Personal Safety System provides the most benefit to belted
occupants. The system monitors and tailors the air bag
deployment based upon safety belt usage. Failure to properly wear
your safety belt will increase your risk of injury.
2004 F150 (f12)
Owners Guide (post-2002-fmt)
USA English (fus)
Seating and Safety Restraints
111