Air Bag Systems: Description and Operation

AIRBAG CONTROL MODULE (ACM)
The Airbag Control Module (ACM) contains the impact sensor and energy reserve capacitor. The impact sensor acts as a threshold sensitive switch that completes a circuit when an impact provides sufficient deceleration. The sensor is calibrated for the specific vehicle and reacts to the severity and direction of the impact.

The ACM monitors the system to determine the system readiness. The ACM stores sufficient energy to deploy the airbags for approximately two minutes after the battery is disconnected. The ACM contains on-board diagnostics, and illuminates the AIRBAG warning lamp in the cluster when a diagnostic trouble code occurs. The warning equipment is tested for a few seconds every time the vehicle is started.

CLOCKSPRING
The clockspring is mounted to the steering column behind the steering wheel. The clockspring consists of a flat, ribbon like, electrically conductive tape that winds and unwinds with the steering wheel rotation.

The clockspring is used to maintain a continuous electrical circuit between the wiring harness and the:
- Driver's airbag module
- Speed control switches
- Horn switch

DRIVER AIRBAG MODULE

WARNING: NEVER DISASSEMBLE THE DRIVER OR PASSENGER AIRBAG MODULES, THERE ARE NO SERVICEABLE PARTS WITHIN THE MODULES.

The Driver Airbag Module located in the center of the steering wheel is the most visible part of the system. It contains the airbag cushion and its supporting components. The airbag module contains a housing in which the cushion and inflator are attached and sealed.

The driver side inflator assembly is mounted from the back of the module housing. When supplied with the proper electrical signal, the inflator assembly produces a gas and discharges it directly into the cushion. A protective cover is fitted to the front of the Driver Airbag Module and forms a decorative cover in the center of the steering wheel. The Driver Airbag Module is mounted directly to the steering wheel.

PASSENGER AIRBAG MODULE

WARNING: NEVER DISASSEMBLE THE DRIVER OR PASSENGER AIRBAG MODULES, THERE ARE NO SERVICEABLE PARTS WITHIN THE MODULES.

The Passenger Airbag Module is located beneath the decorative cover of the instrument panel, facing the passenger seat.

The PAB module is mounted to the instrument panel and pad assembly. The passenger inflator assembly is within the module housing. The module is mounted to the instrument panel retainer and support structure. A protective cover is fitted into the instrument panel over the airbag module and forms a decorative cover.

The Passenger Airbag Module (PAB) consists of:
- Inflator assembly
- Reaction canister
- Airbag Pillow
- Deployment door

When supplied with the proper electrical signal the inflator will produce a gas and discharge it directly into the cushion.

When supplied with the proper electrical signal, the inflator produces gas and discharges it directly into the pillow. The deployment door Will hinge, allowing the pillow to fully inflate.