Air Bag Systems: Description and Operation

SYSTEM OPERATION
Airbag Control Module
The Airbag Control Module (ACM) contains the accelerometer and energy reserve capacitor. The ACM is mounted on the tunnel floor pan, forward of the center console. The accelerometer is located inside the ACM. The accelerometer provides confirmation of a crash, discriminating severity. The ACM monitors the system to determine the system readiness. The ACM ma store sufficient energy to deploy the airbags for only two minutes after the battery is disconnected. The ACM contains on-board diagnostics, and will illuminate the AIRBAG warning lamp on the cluster when a fault 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 is used to maintain a continuous electrical circuit between the wiring harness and the:
- Driver's airbag module
- Speed control switches
- Horn switch
The clockspring consists of a flat, ribbon like, electrically conductive tape which winds and unwinds with the steering wheel rotation.

Driver And Passenger Airbag Modules

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

Driver Airbag Module

Airbag System Component Location:

The Driver Airbag Module is packaged in the steering wheel. It contains the airbag cushion and its supporting components. The drivers airbag module contains a housing to which the cushion and inflator are attached and sealed. A membrane horn switch is integral to the airbag module cover.

The driver side inflator assembly is mounted from the back of the module housing. When supplied with the proper electrical signal the inflator assembly will produce a gas and discharge 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. This cover incorporates the integral horn switch The driver airbag module is mounted directly to the steering wheel.

Passenger
The Passenger Airbag Module is located beneath the instrument panel and pad assembly.

The passenger inflator assembly is within the module housing. The module is mounted to the upper and lower instrument panel. When supplied with the proper electrical signal the inflator will produce a gas and discharge it directly into the cushion. Upon deployment, the instrument panel upper cover will tear open and allow the passenger airbag to fully inflate.

Front Impact Sensor
The Driver and Passenger Airbag System is a supplemental safety device designed to help protect the driver and passenger from serious injury, caused by a frontal impact of the vehicle.

The Airbag Control Module's (ACM) internal impact sensor provides verification of the direction and severity of an impact. The sensor is mounted within the ACM.

The Airbag Control Module (ACM) uses data collected from it's internal accelerometers to discriminate the direction and severity of an impact. The ACM will activate power stages internal to the module in order to deploy the driver and passenger side airbags once a predetermined threshold has been exceeded. The ACM is calibrated for a particular vehicle family and uses an advanced software algorithm to discriminate the severity and direction of any vehicle event.