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Front passenger seat occupied recognition sensor, function - GF91.60-P-1100CWU

MODEL 204.0/2 with CODE (494) USA version up to Model Year 08 

Function requirements: 

Function sequence 

The front passenger seat occupied and automatic child seat recognition are determined via the weight that is on the front passenger seat. The weight is determined by the seat occupied recognition pressure sensor (B48/4); it measures the pressure in a seat mat filled with silicone. The force that is introduced via the seat belt is measured by the belt tension sensor (B48/3) so that weight classification corrections can be made if necessary.

These two measured values are used by the Weight Sensing System (WSS) control unit (N110) to calculate the weight classification and forwarded via interior CAN to the front SAM control unit with fuse and relay module (N10/1) and from there via chassis CAN to the supplemental restraint system control unit (N2/10).

Dependent on the weight classification, the following states are defined:

The signal is also transmitted via interior CAN to the instrument cluster (A1), which shows a message in the multifunction display (A1p13).

Automatic child seat recognition warning lamp (S6/1e1) 

If the front passenger seat is found to be occupied, the automatic child seat recognition warning lamp in the instrument panel switch group (S6/1) is switched off.

If the front passenger seat is found not to be occupied, the automatic child seat recognition warning lamp remains switched on as long as no occupation is found.

If a low weight is detected and the seat belt is buckled, the automatic child seat recognition warning lamp is also switched on.

REFER TO SYSTEM WIRING DIAGRAMS Electrical function diagram, supplemental restraint system (SRS)   PE91.60-P-2052-99FAA
  Belt tension sensor component description B48/3 GF91.60-P-4108CWU
  Seat occupied recognition pressure sensor, component description B48/4 GF91.60-P-4067CWU
  Supplemental restraint system control unit, component description N2/10 GF91.60-P-4068CW
  Front SAM control unit with fuse and relay module, component description N10/1 GF54.21-P-6070CW
  Weight Sensing System (WSS) control unit, component description N110 GF91.60-P-4069CWU