Restraints and Safety Systems: Description and Operation

Occupant restraints for this vehicle include both Active and Passive types. Active restraints are those which require the occupants to take some action to employ, such as fastening the seat belt; while Passive restraints require no action by the occupants to be employed.

ACTIVE RESTRAINTS
The Active restraints include:
Front Driver and Passenger Seat Belts - Both seating positions are equipped with a three-point restraint. Seat Belt Tensioners (SBT) that actuate to remove slack in the seat belts and to snug the occupant into the seat at the onset of an impact event. This controls the occupant's forward movement to reduce the likelihood of injury as a result of contacting any interior components. Especially during the primary impact event phase, the tensioning power of the SBTs guarantees optimum transmission of the passenger compartment deceleration to the passenger. The vehicle's SBTs employ load-limiting retractors that "give" with higher seat belt loads. If a given seat belt force is exceeded, the seat belt force limiter permits a controlled forward inclination of the occupant's upper body. This protective function reduces the risk of chest and shoulder injuries and permits the passenger to plunge deeper into the airbag for a smooth dissipation of the occupant's kinetic energy. The drivers SBT is mounted in the B pillar below the belt line which locks only as a result of a sudden vehicle stop or a rapid extension of the webbing. This is called "Emergency Locking", it will allow free movement under normal driving conditions. To allow the retention of a child seat, a dual-mode passenger SBT is mounted in the B pillar below the belt line and can be switched between "Emergency Locking" and "Automatic Locking". Seat-mounted, inboard buckles allow seat adjustment while maintaining
a consistent relationship between the buckle and the seat belt. For easy and consistent access and adjustment, a free-running latch plate on each belt slides along the webbing and stops against a button near the occupant's shoulder when unfastened. A seat belt warning lamp in the Instrument Cluster (IC) comes on and a warning chime sounds for a short time if the driver's seat belt is not fastened when the ignition switch is turned to the "RUN" position. After starting the engine, the seat belt warning indicator flashes briefly as an added precaution.

Child Restraint Anchors - The front passenger seat includes a LATCH (Lower Anchors and Tether for Children) child seat anchorage system. LATCH-compatible child seats are those engineered for retention by direct attachment to the vehicle's seat structure rather than with the vehicle's seat belts. The child seat's lower anchors attach to the seat structure via heavy-gauge wire loops at the intersection of the seat cushion and seat back. The child seat's upper tether strap attaches to a child seat tether anchor. Child seats can also be securely fastened in the passenger seat using the seat belts. For this purpose, the passenger seat belt includes a dual-mode SBT. After the child seat is positioned and the belt routed according to instructions for the child seat, the seat belt is pulled all the way out of the SBT to the end of its travel. This switches the SBT to the "Automatic Locking" mode. As the seat belt retracts, the SBT locks to prevent the belt from being pulled out again. Pulling the belt snugly over the child seat secures the seat in place. When the belt retracts fully after child seat removal, normal "Emergency Locking" action is restored to the SBT.

PASSIVE RESTRAINTS




The passive restraints include:
Driver and Passenger Front Airbags - This airbag system is a passive, inflatable, Supplemental Restraint System (SRS). Vehicles with this equipment can be readily identified by the "SRS AIRBAG" logo molded into the driver airbag trim cover in the steering wheel (1) and also into the passenger airbag area (2) of the instrument panel top pad above the glove box.




Vehicles with the SRS can also be identified by the Airbag Warning Indicator, which will illuminate in the Instrument Cluster (IC) for about six seconds as a bulb test each time the ignition switch is turned to the "RUN" position.

The Supplemental Restraint System (SRS) also includes the following major components.




Occupant Restraint Controller (ORC) - The Occupant Restraint Controller (ORC) is located on a mount on the top of the transmission tunnel (2) in front of the shifter, under the front center console.

ORC System Logic - The Supplemental Restraint System (SRS) uses an impact severity level (threshold) to determine the appropriate response from the ORC. Impacts that exceed the initial threshold in frontal, front-angled, and rear impacts trigger only the SBT that have the seat belt fastened. If the seat belt is not fastened, the system will not recognize the belt and not trigger the SBT. But, if the impact is severe enough, the airbags will be triggered even if the seat belts are not fastened. Impacts that exceed the higher threshold always trigger the airbags. The driver and passenger SRS systems operate independently of one
another based on seat belt use. SBT actuation occurs only if the seat belts are buckled. After an impact that activates an SBT, the SBT assembly must be replaced. The ORC monitors operational readiness of the SRS and illuminates the airbag warning indicator lamp in the Instrument Cluster (IC) if a malfunction should occur. The following system components are monitored or undergo a self-check at startup. The side-impact sensor, airbag ignition circuits (squibs), seat belt buckle switches and the SBT. The airbag warning indicator lamp also illuminates briefly each time the engine is started, allowing the driver to verify its operation.




Airbag Warning Indicator Lamp - The airbag warning indicator lamp is integral to the Instrument Cluster (IC), which is located on the Instrument Panel (IP) in front of the driver.




Clockspring - The clockspring is located at the top of the steering column, directly beneath the steering wheel where it is attached to the column by two screws (1).




Driver Front Airbag - The driver front airbag (1) is located in the center of the steering wheel, as part of the steering wheel trim cover.




Passenger Front Airbag - The passenger front airbag (1) is located on the instrument panel structural duct, beneath the instrument panel top pad and above the glove box.




The passenger front air bag can be deactivated when a child seat or small child occupies that seat by using the ignition key to turn the switch (1) to the OFF position. This will illuminate the passenger airbag OFF warning lamp on the center console. This indicates that the passenger front airbag is deactivated. The passenger front airbag will not be activated until the switch is turned to the ON position and the passenger airbag OFF warning lamp goes out.




The passenger airbag off warning lamp (1) in the center console illuminates when the air bag is deactivated.




Side Impact Sensor - Two side impact sensors (2) are installed, one left side and one right side. The sensors are mounted on the body cross brace in the center of the door sill plates directly under the carpet.




Side Impact Airbag - The side impact airbags are concealed behind the door trim panels above the armrest. The side impact airbag is riveted (1) to the door's interior structure and activated by a squib (2). SRS logos on the trim panels denote the presence of the airbags. If the airbag is triggered during a lateral collision, the airbag tears open a seam on the inner door trim and inflates within 0.007 seconds to form a protective cushion between the passenger and the door. Thus the impact on the passenger's thorax and the ejecting motion of the head, which might otherwise cause serious injuries, are reduced.

The ORC and the Instrument Cluster (IC) each contain a central processing unit and programming that allow them to communicate with each other using the Controller Area Network (CAN). This method of communication is used by the ORC for control of the airbag indicator lamp.

Hard wired circuitry connects the SRS components to each other through the electrical system of the vehicle. These hard wired circuits are integral to several wire harnesses, which are routed throughout the vehicle and retained by many different methods. These circuits may be connected to each other, to the vehicle electrical system, and to the SRS components through the use of a combination of soldered splices, splice block connectors, and many different types of wire harness terminal connectors and insulators. Refer to the appropriate wiring information. The wiring information includes wiring diagrams, proper wire and connector repair procedures, further details on wire harness routing and retention, as well as pin-out and location views for the various wire harness connectors, splices and grounds.

ACTIVE RESTRAINTS
The primary passenger restraints in this or any other vehicle are the standard equipment factory-installed seat belts and child restraint anchors. Seat belts and child restraint anchors are referred to as an active restraint because the occupants are required to physically fasten and properly adjust these restraints in order to benefit from them. See the vehicle glove box for more information on the features, use, and operation of all of the factory-installed active restraints.

PASSIVE RESTRAINTS




The driver/passenger airbags and the driver/passenger Seat Belt Tensioners (SBT) were designed to reduce the risk of an injury to the chest and head in the event of a head-on collision.

The side airbags were designed to protect primarily the upper body and also to help protect the head in the event of a side collision.

Malfunctions in the SRS system are indicated on the Instrument Cluster (IC) by the airbag warning indicator lamp.