Theory Of Operation

A Supplemental Restraint System (SRS) is standard factory installed safety equipment on this vehicle. Available supplemental occupant restraints for this vehicle include both Active  and Passive  types. Active restraints are those which require the vehicle occupants to take some action to employ, such as fastening and adjusting a seat belt; while passive restraints require no action by the vehicle occupants to be employed.

The Occupant Restraint Controller (ORC) and the Instrument Panel Cluster (IPC) each contain a micro controller and programming that allow them to communicate with each other using the Controller Area Network (CAN) data bus. This method of communication is used by the ORC for control of the airbag indicator in the IPC.

ACTIVE RESTRAINTS 

The primary passenger restraints in this vehicle are the standard equipment factory installed seat belts for the front, second row, third row, and child restraint anchors. Seat belts and child restraint anchors are referred to as an active restraint because the vehicle occupants are required to physically fasten and properly adjust these restraints in order to benefit from them.

PASSIVE RESTRAINTS 

The passive restraints are referred to as a SRS components because they were designed and are intended to enhance the protection for the occupants of the vehicle only  when used in conjunction with the seat belts. They are referred to as passive restraints because the vehicle occupants are not required to do anything to make them operate; however, the vehicle occupants must be wearing their seat belts in order to obtain the maximum safety benefit from the factory installed SRS components.

The components that make up the passive restraints are the:

• Airbag Indicator
• Adaptive Load Limiters
• Clockspring
• Dual Multistage Front Airbags
• Knee Airbags
• Seat Airbags
• Side Curtain Airbags
• Front Impact Sensors
• Occupant Classification System
• Occupant Detection Sensor
• Seat Belt Tensioners
• Seat Track Position Sensors
• Side Impact Sensors

The SRS electrical circuits are continuously monitored and controlled by a micro controller and software contained within the ORC. An airbag indicator in the IPC illuminates from four to six seconds as a bulb test each time the status of the ignition transitions to ON or START. Following the bulb test, the airbag indicator is turned ON or OFF by the ORC to indicate the status of the SRS. If the airbag indicator comes ON at any time other than during the bulb test, it indicates that there is a problem in the SRS electrical circuits. Such a problem may cause airbags not to deploy when required, or to deploy when not required.

For additional information regarding the description and operation of the Restraints System. Refer to RESTRAINT SYSTEM, DESCRIPTION AND OPERATION .