Airbag Control Module (SRS Module)

It usually sits in the centre of the car and contains its own acceleration sensors; satellite sensors in the doors and front add information. It stores crash data and fault codes, often in a way that cannot be cleared after a deployment. A capacitor in the module keeps it working briefly if power is lost in the crash.

The module continuously checks the system and compares crash sensor signals with deployment thresholds.

After a deployment the module often must be replaced or reset by a specialist. An SRS warning light means the module has detected a fault.