Seat Belt Systems: Description and Operation

GF91.40-P-2001R Seat Belt Lock System Function

General
The emergency tensioning retractor units on the front seats are equipped with a solenoid controlled seat belt lock system, in which the belt extension can be blocked depending on vehicle deceleration and vehicle inclination.

Function requirements:
^ C. 15R On

Function
The vehicle-sensitive seatbelt lock sensor (A60) is connected via the left front seat adjustment control unit with memory (N32/1) with the left front seat belt lock adjusting solenoid (Y96) and via the right front seat adjustment control unit with memory (N32/2) with the right front seat belt lock adjusting solenoid (Y96/1).

If the vehicle deceleration exceeds 0.45 g or if the vehicle inclination is > 27°, the vehicle-sensitive seatbelt lock sensor actuates the solenoids for the seat belt lock via the front seat adjustment control units, blocking the belt extension.

The front seat adjustment control units also constantly receive a continuous signal over 2 discrete lines from the vehicle-sensitive seatbelt lock sensor and thus recognize immediately when a fault occurs in the actuation circuits of the seat belt lock solenoids. Fault incidents are displayed in the instrument cluster (A1) by the airbag indicator and warning lamp (A1e15).