Seating position sensor (only E88)

According to the regulations of the FMVSS (Federal Motor Vehicle Safety Standard), a 5 %- woman must be distinguished from a 50 % man on the driver's seat. The seating position sensor detects the airbag range designed for a person with regard to the seat adjustment in longitudinal direction.

Fig 1: Removing Seating Position Sensor

Courtesy of BMW OF NORTH AMERICA, INC.

The seating position sensor is a Hall sensor and it is supplied with voltage via the ACSM control unit. The current intensity changes depending on the distance of the seat position switch to the magnet holder.

Fig 2: Seating Position Sensor - Circuit Diagram

Courtesy of BMW OF NORTH AMERICA, INC.

The signal of the seating position sensor also influences the delayed triggering of stage 2 of the inflator assembly (driver's and front passenger's airbag).