Seat Belt Systems: Description and Operation

SEAT BELT SYSTEM DESCRIPTION AND OPERATION

FASTEN SAFETY BELT INDICATOR
- The IPC illuminates the fasten safety belt indicator when the body control module (BCM) detects that the driver's seat belt is unbuckled. The IPC receives a discrete input from the BCM requesting illumination. When this indicator is on the BCM activates the audible warning.
- The IPC performs the displays test at the start of each ignition cycle. The IPC illuminates the fasten safety belt indicator.

RESTRAINT SYSTEM
Seat belts are the primary means of occupant restraint. Seat belts help to keep the occupants inside the passenger compartment and to gradually reduce the impact forces during the following events:
- Frontal impact type crashes
- Rear impact type crashes
- Side impact type crashes
- Roll-over type crashes

All seat belt retractors have emergency locks. The retractors remain unlocked during normal operation and under normal driving conditions. The retractors remain unlocked during normal conditions in order to allow free movement of the upper body of each occupant. A pendulum locks the seat belt webbing into position. The pendulum causes a locking bar to engage a cog on the spool of the retractor mechanism when the following conditions occur:
- A rapid extraction of the seat belt webbing from the retractor
- An abrupt change in the vehicle speed
- An abrupt change in the vehicle direction
- Operation of the vehicle on a steep upgrade
- Operation of the vehicle on a steep downgrade

The retractable seat belts, except for the driver seat belt, have an automatic locking feature, or cinch feature. The cinch feature is recommended for securing a child seat. The cinch feature is engaged by fully extending the seat belt from the retractor. Once engaged, the seat belt can retract, but cannot be extended again until the cinch feature is cancelled. The cinch feature is cancelled when the seat belt has fully retracted.

This vehicle is also equipped with a supplemental inflatable restraint (SIR) system. Refer to SIR System Description and Operation in Restraint Systems.

FRONT SEAT BELT SYSTEM
The front seat belt system includes the following components:
- The driver and the passenger seat belt retractors, located on the center pillar post and attached to the floor panel
- The driver and passenger seat belt buckles, located between the two front seats and attached to each seat
- The driver seat belt switch, located in the driver seat belt buckle and controls the fasten safety belt indicator and a tone alarm

REAR SEAT SYSTEM
The rear seat belt system includes the following components:
- The rear seat belt retractors, located at the inner wheelhouse panel and attached to the floor panel by the rear seat shoulder belt retractor bracket
- The rear seat belt buckles, attached to each seat