Seat Position Sensor: Description and Operation

Seat-Position Sensor

Seat-position sensor
The installation of the seat-position sensor is dependent on the national-market version.
In the US version, according to the regulations of the FMVSS (Federal Motor Vehicle Safety Standard), a 5th percentile woman must be distinguished from a 50th percentile 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. The signal of the seat position influences the time-delayed activation of the second stage of the gas generator (driver's airbag).

Functional description
The seat-position sensor is designed as a hall effect sensor. The current intensity changes depending on the distance of the seat position sensor to the magnet holder.
Using this measurement current, the airbag control unit detects the seat adjustment in the longitudinal direction..







Structure and inner electrical connection
The seat-position sensor has a 2-pin plug connection.
The airbag control unit supplies the seat-position sensor with voltage.
The seat-position sensor has a reverse polarity protection







Nominal values
Please observe the following setpoint values for the seat-position sensor:

Size Value
Voltage supply 4 to 16 volts

Measurement current for the 12 to 19 mA
area of the seat position 50th
percentile man

Measurement current for the 1.9 to 6 mA
area of the seat position 5th
percentile woman

Temperature range -40 °C to 85 °C

Diagnosis instructions

Failure of the component
If the seat-position sensor fails, the following behavior is to be expected:
- Fault entry in the airbag control unit
- Airbag indicator light in the instrument cluster lights up

We can assume no liability for printing errors or inaccuracies in this document and reserve the right to introduce technical modifications at any time.