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Seat Occupant Sensor: Description and Operation




The occupancy sensor locations are identical for both the coupe and convertible, except that since the convertible has no 'B' post, the equivalent sensor is mounted in the rear quarter trim capping. The four sensors are strategically placed to detect the presence and movement of the passenger front seat occupant.

The occupancy sensor system uses ultrasound at an operating frequency of 40 kilohertz to monitor passenger front seat occupancy. The SRS uses four ultrasonic sensors, one at the A-post, one at the 'B' post and two in the roof console. The sensors determine the presence and position of the passenger front seat occupant with respect to the passenger air bag deployment door. The sensors determine air bag module deployment decisions by classifying occupants as either 'in position' or 'out of position'. The sensors are part of a system that is sophisticated enough to be unaffected by body extremities (hands and feet) and respond only to head or body movements.

Obstruction of any sensor for an extended period of time, or repeated key cycles will cause the system to log a 'blocked' code and will illuminate the SRS indicator. Subsequent clearance of the obstruction will reinstate the SRS indicator, but the code will remain logged.