Air Bag Control Module: Description and Operation

Diagnostic Monitor

The diagnostic monitor assembly contains a microcomputer that monitors the electrical system components and connections. The monitor performs a self-check of the microcomputer internal circuits and energizes the system readiness indicator lamp during prove out and whenever a fault can be detected and translated into coded lamp displays. If certain faults occur, the system will be disarmed by a firing disarm device built into the monitor. If a system fault exists and the lamp is malfunctioning, an audible tone will be heard indicating the need for service.

Tone Generator

The air bag readiness lamp is the prime means of determining the air bag system condition. However, a series of five sets of five tones will be heard if the readiness lamp is out and a fault occurs in the system. This also means that the Supplemental Driver Air Bag System is in need of service. Unless serviced, the Supplemental Driver Air Bag Restraint System may not function properly in the event of an accident.