Air Bag Control Module: Description and Operation

PURPOSE
The diagnostic monitor contains a microcomputer that monitors the airbag electrical system components and connections. The monitor performs a self-check of the microcomputer internal circuits and energizes the system readiness during prove out and whenever a fault occurs.

OPERATION
Airbag system electrical faults are detected and translated into coded indicator displays. When a certain fault occurs, the microcomputer disables the system by opening a thermal fuse built into the monitor. If an airbag system fault occurs and the indicator is malfunctioning, an audible tone will be heard signaling the need for service.

A backup power supply is built into the diagnostic monitor to provide airbag deployment power if the battery or battery cables are damaged in an accident prior to the crash sensors closing. The backup power supply stored energy will be depleted approximately one minute after the positive cable of the battery is disconnected.

WARNING: THE BACKUP POWER SUPPLY ENERGY MUST BE DEPLETED BEFORE ANY AIR BAG COMPONENT SERVICE IS PERFORMED.