Air Bag, Seat: Operation

Each front Seat AirBag (SAB) is deployed individually by an electrical signal generated by the Occupant Restraint Controller (ORC) to which it is connected through left or right SAB line 1 and line 2 (or squib) circuits. When the ORC sends the proper electrical signal to the pyrotechnic-type Micro Gas Generator (MGG) inflator, the electrical energy generates enough heat to initiate a small pyrotechnic charge which ignites chemical pellets within the inflator.

Once ignited, these chemical pellets burn rapidly and produce a large quantity of inert gas. The inflator is sealed to the SAB cushion and a diffuser in the inflator directs all of the inert gas into the folded SAB cushion, causing the cushion to inflate. As the cushion inflates it will split the fabric wrap, the pouch (intensifier) integral to the seat back trim cover and the outboard side of the seat back trim cover. The cushion then expands into the area between the outboard side of the front seat and the front door to form a cushion to protect the front seat occupant during a side impact collision or a vehicle rollover incident.

Following the front SAB deployment, the cushion slowly deflates by venting the inert gas through the loose weave of the cushion fabric, and through a vent in the cushion. After venting is achieved, the deflated cushion hangs down loosely from the outboard side of the front seat back.

The ORC monitors the condition of the front seat airbags through circuit resistance. If any fault is detected, the ORC will illuminate the airbag indicator in the instrument cluster and store a Diagnostic Trouble Code (DTC). Proper diagnosis of the MGG SAB inflator and squib circuits requires the use of a diagnostic scan tool and may also require the use of the Airbag Kit. Refer to the appropriate diagnostic information.