F 150 Super Crew 2WD V8-4.6L SOHC VIN 6 (2003)
Seat Belt Tensioner: Description and Operation
Pretensioner System
All F150s have a pretensioner system for the front outboard occupants. The front outboard safety belt retractors or the front outboard safety belt
buckles use a pretensioner system. This works in conjunction with the front air bag system mounted in the steering wheel and instrument panel.
If the vehicle is involved in a collision that results in deployment of the front air bags and safety belt pretensioners, a new driver and passenger seat
belt system (including safety belt buckle and pretensioners or safety belt retractor and pretensioners, safety belt retractors, safety belts, buckles and
height adjusters), must be installed.
For diagnostic information, refer to Air Bag Systems.
For pretensioner retractor disposal information, refer to Air Bag Systems.
Safety Belt Pretensioners
As part of the supplemental restraint system (SRS), the vehicle is equipped with one of two types of safety belt pretensioners. The pretensioners are
activated by the restraints control module (RCM) when the module detects a crash event force exceeding a programmed limit.
Safety Belt Buckle and Pretensioner
SuperCab vehicles with seat integrated restraints (SIR) are equipped with safety belt buckle and pretensioner. These are for the front outboard
occupants, located on the inboard side of the seats. To identify a SIR seat, see Seat Integrated Restraints (SIR) Identification.
The safety belt buckle and pretensioner is a pyrotechnic device that removes excess webbing from the safety belt system. When the front air bag
system is deployed, the pretensioner in the buckle deploys, causing the buckle to move downward, pulling excess webbing from the lap and shoulder
safety belts.
Safety Belt Retractor and Pretensioner
Vehicles without seat integrated restraints (SIR) are equipped with safety belt retractor and pretensioners, for the front outboard occupants. To identify
a SIR seat, refer to Seat Integrated Restraints (SIR) Identification.
When the front air bag system is deployed, the pretensioner in the retractor deploys, causing the retractor spool to rotate. The rotating spool action
removes excess webbing from the safety belt assembly, tightening the webbing around the occupant.
