Seat Occupant Sensor: Description and Operation

SRS CONTROL SYSTEM

PASSENGER PRESENCE DETECT SENSOR (PPD)

DESCRIPTION




The passenger presence detection system detects the presence of passenger in the seat. The system is designed primarily to prevent replacement of airbag components that fire needlessly in an accident. The PPD system consists of a weight sensor and an interface unit. The threshold for PPD is ; occupied (15 kg), not occupied (0.6 kg) The sensor characteristics is defined :

RP <= 50 k Ohm for W => 15 kg
RP > 50 k Ohm for W < 0.6 kg
(RP : Resistance of force sensing resistor)
(W : Mass of weight)