Passenger Air Bag - Operation

OPERATION

The passenger airbag is deployed by an electrical signal generated by the Occupant Restraint Controller (ORC) (also known as the lowline or highline airbag control unit/ARCADE) through the passenger airbag squib circuits to the initiator in the airbag inflator. The hybrid-type inflator assembly contains a small canister of highly compressed inert gas. When the ORC sends the proper electrical signal to the airbag inflator, the electrical energy creates enough heat to ignite chemical pellets within the inflator.

Once ignited, these chemical pellets burn rapidly and produce the pressure necessary to rupture a containment disk in the inert gas canister. The inflator and inert gas canister are sealed to the back of the airbag housing and a diffuser in the inflator directs all of the inert gas into the folded airbag cushion, causing the cushion to inflate. As the cushion inflates, the passenger airbag door will split at a predetermined tear seam lines concealed on the inside surface of the door, then the door will pivot up over the top of the instrument panel and out of the way. Following an airbag deployment, the airbag cushion quickly deflates by venting the inert gas through the loose weave of the fabric used to construct the back (instrument panel side) of the airbag cushion.

Some of the chemicals used to create the inert gas may be considered hazardous while in their solid state before they are burned, but they are securely sealed within the airbag inflator. However, the gas that is produced when the chemicals are burned is harmless. A small amount of residue from the burned chemicals may cause some temporary discomfort if it contacts the skin, eyes, or breathing passages. If skin or eye irritation is noticed, rinse the affected area with plenty of cool, clean water. If breathing passages are irritated, move to another area where there is plenty of clean, fresh air to breath. If the irritation is not alleviated by these actions, contact a physician immediately.

Proper diagnosis of the passenger airbag inflator and the passenger airbag squib circuits requires the use of a diagnostic scan tool. Refer to the appropriate diagnostic information.