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B-Pillar Sensor

The B-pillar airbag sensor consists of a longitudinal acceleration sensor and a transverse acceleration sensor.

The acceleration sensors measure both the acceleration and the deceleration in the X and Y directions. The resultant from the X and Y signals is the definitive factor in determining the direction of the impact.

The B-pillar airbag sensors serve the purpose of detecting head-on, side and rear-end collisions.

The B-pillar airbag sensors on the left and right are of identical design and are allocated by way of mechanical coding during installation.

Fig 1: Identifying B-Pillar Sensor
G06925589Courtesy of BMW OF NORTH AMERICA, INC.