Seat Occupancy Sensor (SBE)
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An occupancy sensor pad is incorporated into the front passenger's seat cushion. The pad is a foil contact sensor that is open when the seat is not occupied. When the seat cushion is pressed by the weight of a passenger, the sensor circuit produces a resistance that varies with the weight and/or movement.
This variable resistance signal is input to the Seat Occupancy Module (SBE). The SBE is a small signal converter module, mounted under the passenger's seat. It converts the analog signal, from the seat pad into a square wave modulated output signal that is sent to the MRS control module. The MRS control module uses this signal for air bag triggering in the event of a collision.