Front Impact Sensors
The front impact sensors are electronic accelerometers that sense the rate of vehicle deceleration. Front impact sensors and the ACM Accelerometer provide verification of the direction and severity of a front impact to the ACM processor.
The front impact sensors receive battery current and ground from he ACM through dedicated sensor signal and ground circuits. The ACM communicate with the front impact sensors by modulating the current in the sensor signal circuit. Each sensor communicates the sensor status as well as sensor fault information to the microprocessor in the Airbag Control Module.
The ACM microprocessor continuously monitors all circuits to determine the system readiness. If the ACM detects a system fault, it sets a Diagnostic Trouble Code and controls the airbag warning indicator operation accordingly. When needed the driver and passenger airbags are deployed by the ACM to provide side impact protection for the occupants.
WARNING:
THE AIRBAG SYSTEM IS A SENSITIVE, COMPLEX ELECTROMECHANICAL UNIT. BEFORE ATTEMPTING TO DIAGNOSE OR SERVICE ANY AIRBAG SYSTEM OR RELATED STEERING WHEEL, STEERING COLUMN, OR INSTRUMENT PANEL COMPONENTS YOU MUST FIRST DISCONNECT AND ISOLATE THE BATTERY NEGATIVE (GROUND) CABLE. WAIT TWO MINUTES FOR THE SYSTEM CAPACITOR TO DISCHARGE BEFORE FURTHER SYSTEM SERVICE. THIS IS THE ONLY SURE WAY TO DISABLE THE AIRBAG SYSTEM. FAILURE TO DO THIS COULD RESULT IN ACCIDENTAL AIRBAG DEPLOYMENT AND POSSIBLE PERSONAL INJURY OR DEATH.
WARNING:
NEVER STRIKE OR KICK THE AIRBAG CONTROL MODULE, AS IT CAN DAMAGE THE INTERNAL ACCELERATION SENSOR OR AFFECT ITS CALIBRATION. IF AN AIRBAG CONTROL MODULE OR SIDE IMPACT SENSOR IS ACCIDENTALLY DROPPED DURING SERVICE, THE MODULE OR SENSOR MUST BE SCRAPPED AND REPLACED WITH A NEW UNIT. FAILURE TO TAKE THE PROPER PRECAUTIONS COULD RESULT IN ACCIDENTAL AIRBAG DEPLOYMENT AND PERSONAL INJURY OR DEATH.
CAUTION:
Do not remove or install the impact sensors while the sensor is attached to the vehicle wiring.