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Seat Position Sensors (USA/CDN Only)

Fig 1: Identifying Seat Position Sensors (USA/CDN Only)
GLL117761Courtesy of VOLVO CARS OF NORTH AMERICA.

The seat position sensor is used to determine the size of the person sitting on the seat. There are two seat position sensors in the vehicle - one under the driver's seat and one under the front passenger seat. The seat position sensors are directly connected to the supplemental restraint system module (SRS). The seat position sensors have separate signal cables to the control module and a common ground.

The seat position sensors comprise a Hall sensor that changes current strength based on the position of the seat. The seat position sensor has two classifications - small person or large person. Small person indicates that the seat is approx. 10 cm (4 in) or less from the front-most seat position. All other positions are classified as large person.

This information is used by the function for adaptive seatbelt force limiting.