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Seat Occupant Sensor: Description and Operation




Seat Occupancy Detection




Seat occupancy detection mats are installed in the seat cushion of the driver and passenger seat and if equipped with optional rear airbags, they are also used in the left and right rear seats.

The sensor mat is identical to the mats used in previous models for the MRS systems. The sensor system consists of pressure sensors that use an electronic evaluation unit (SBE) to detect whether there is weight on the seat.

As of a weight of approx.12 kg (26.4 lbs.),the seat is recognized as occupied. The electronic evaluation units of the seat occupation mats are connected to the relevant satellites.(SSFA/SSBF=sensors for front seat, SSH=sensors for rear seat)




The information regarding seat occupation is required for activation of the following functions:

- Airbag activation
- Activation of the seatbelt tensioners and/or end fitting tensioners
- Triggering the active head restraints
- Automatic positioning of the rear head-restraints