Passenger-side seat occupied recognition function - GF91.60-P-1100FLU

MODEL 212 with CODE U10 (Front passenger seat with weight sensor) 

Function requirements, general 

• Circuit 15R ON

The status of circuit 15R is sent by the electronic ignition lock control unit (N73) via chassis CAN (CAN E) (up to 28.2.13) or via chassis CAN 1 (CAN E1) (as of 1.3.13) to the supplemental restraint system control unit (N2/10).

Passenger-side seat occupied recognition, general 

The passenger-side seat occupied recognition detects whether the front passenger seat is occupied.

The passenger-side seat occupied recognition function includes the following subfunctions:

• Function sequence for front passenger seat occupied recognition (up to 28.2.13) 
• Function sequence for front passenger seat occupied recognition (up to 1.3.13) 
• Function sequence for outputting status and fault messages 

Function sequence for front passenger seat occupied recognition (up to 28.2.13) 

The front passenger seat occupied recognition and automatic child seat recognition are determined by means of the weight that is on the front passenger seat. The weight is determined using a pressure measurement from the seat occupied recognition pressure sensor (B48/4) in a silicone-filled seat mat. 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 determine a classification for the applied weight. The status of the seat occupied recognition is sent by the WSS control unit via interior CAN (CAN B), front SAM control unit with fuse and relay module (N10/1) and chassis CAN to the supplemental restraint system control unit.

The following conditions are defined depending on the weight classification:

• Seat not occupied
• Seat occupied:
  • Light weight (e.g. child seat)
  • Person recognized

Function sequence for front passenger seat occupied recognition (up to 1.3.13) 

The front passenger seat occupied recognition and automatic child seat recognition are determined by means of the weight that is on the front passenger seat. In order to do this, the WSS control unit measures the pressure in a silicone-filled seat mat. The force that is introduced via the seat belt is measured by the belt tension sensor so that weight classification corrections can be made if necessary. Classification of the weight that is present is carried out by the WSS control unit using these two measurements. The status of the seat occupied recognition is sent by the WSS control unit to the supplemental restraint system control unit over the seat occupied recognition LIN (LIN E2).

The following conditions are defined depending on the weight classification:

• Seat not occupied
• Seat occupied:
  • Light weight (e.g. child seat)
  • Person recognized

Function sequence for outputting status and fault messages 

The output of status and fault messages partial function includes the following subfunctions:

• Function sequence for outputting status messages 
• Function sequence for outputting fault messages (up to 28.2.13) 
• Function sequence for outputting fault messages (as of 1.3.13) 

Function sequence for outputting status messages 

The status messages are output via the automatic child seat recognition warning lamp (S6/1e1) in the instrument panel switch group (S6/1) (up to 28.2.13) or via the automatic child seat recognition warning lamp (N72/1e1) (as of 1.3.13) in the upper control panel control unit (N72/1).

The automatic child seat recognition warning lamp is switched on under the following conditions:

• With a front passenger seat recognized as not occupied.
• With a recognized low weight on the front passenger seat and also a fastened seat belt.

The request to switch on the automatic child seat recognition warning lamp is sent by the Supplemental Restraint System control unit over the chassis CAN (up to 28.2.13) or over chassis CAN 1 (as of 1.3.13) to the front SAM control unit. The front SAM control unit actuates the automatic child seat recognition warning lamp accordingly via instrument panel LIN (LIN 1).

With a front passenger seat recognized as occupied, the automatic child seat recognition warning lamp is not switched on.

Function sequence for outputting fault messages (up to 28.2.13) 

Faults or malfunctions that occur during seat occupied recognition are transmitted by the WSS control unit via the interior CAN to the instrument cluster (A1), which displays an appropriate message on the multifunction display (A1p13).

Function sequence for outputting fault messages (as of 1.3.13) 

Faults or malfunctions that occur during seat occupied recognition are transmitted by the WSS control unit via the seat occupancy LIN, the supplemental restraint system control unit, chassis CAN 1, the front SAM control unit and the interior CAN to the instrument cluster, which displays an appropriate message on the multifunction display.