Power supply circuit (booster circuit, backup power supply): Provides and maintains power when battery voltage is low or in case of power supply damage due to a collision.

Front impact G sensors and side impact G sensor: Detect impact to the SRS unit as acceleration and converts it to an electrical signal.

Rollover judgment circuit: Predicts an impending rollover using signals such as the one from the G sensor located inside of the SRS unit. Based on the rollover judgment and the seat belt buckle switch status, the circuit determines whether the seat belt tensioners and the side curtain airbags should deploy or not.

Microprocessor: An impact decision algorithm decides whether or not the collision signal warrants deployment of the airbags or the tensioners.

Diagnostic circuit: Performs self-diagnosis to determine whether system abnormalities are present. If an abnormality is detected, the SRS indicator in the gauge control module turns on.

Non-volatile memory: Records fault conditions. The SRS memories are not erased even if the 12 volt battery terminal is disconnected.

Communication circuit: Circuit for outputting or deleting memory contents.

The SRS unit receives the load information from the weight sensors, performs an occupant judgment of the front passenger's seat, and adjusts the front passenger's airbag deployment and performance.