Passenger-Side Seat Occupied Recognition Function - GF91.60-P-1100FR

Model 257, 290 Up To Model Year 2021 

Function requirements, general 

• Circuit 15R ON

The electronic ignition lock control unit (N73) sends the status of circuit 15 over the user interface CAN (CAN HMI) 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 seat occupied recognition (except CODE U10 (Automatic front passenger airbag shutoff)) 
• Function sequence for seat occupied recognition (with CODE U10 (Automatic front passenger airbag shutoff)) 
• Function sequence for issuing status and fault messages (with CODE U10 (Automatic front passenger seat shutoff)) 

Function sequence for seat occupied recognition (except CODE U10 (Automatic front passenger airbag shutoff)) 

Occupancy of the front passenger seat is recorded by the front passenger seat occupied recognition (B41/1). The status "Seat occupied" or "Seat not occupied" can be detected. The supplemental restraint system control unit reads in the relevant signals of the front passenger seat occupancy recognition.

The occupancy status of the front passenger seat has no influence on the triggering behavior of the Supplemental Restraint System. The occupancy status is only required by the instrument cluster (A1) for the seat belt reminder warning function.

Function sequence for seat occupied recognition (with CODE U10 (Automatic front passenger airbag shutoff)) 

Occupation of the front passenger seat by a person or a child seat is determined by the weight, which is applied to the front passenger seat. For this purpose, the weight sensing system (WSS) control unit (N110) measures the pressure of a seat mat filled with silicone. Based on this value, the WSS control unit classifies the weight that is applied to the seat. The WSS control unit transmits the status of the seat occupancy recognition via the seat occupied recognition LIN (LIN E2) 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

Additional function requirements for issuing status and fault messages (with code U10 (Automatic front passenger airbag shutoff)) 

• Indicator lamp self-test completed successfully

Function sequence for issuing status and fault messages (with CODE U10 (Automatic front passenger seat shutoff)) 

The occupancy status of the front passenger seat is shown as follows:

• Front passenger seat occupied (front passenger airbag activated):

  Front passenger airbag ON indicator lamp (N72/1e2) lights up for approx. t = 60 s.

• Front passenger seat not occupied or child seat detected (front passenger airbag inactive):

  Front passenger airbag OFF indicator lamp (N72/1e1) illuminates permanently.

The supplemental restraint system control unit sends the relevant request over the user interface CAN, head unit (A26/17), telematics CAN (CAN A), Audio/COMAND control panel (A40/9) (except code 446 (Touchpad only)) or touchpad (A105) (with code 446 (Touchpad only)) and the LCP-LIN (LIN A3) to the upper control panel control unit (N72/1) which then actuates the corresponding indicator lamp for the front passenger airbag directly.

Fault messages 

The following indicator lamps are switched on in the event of a fault (e.g. WSS control unit defective, faulty connection to supplemental restraint system control unit):

• Supplemental Restraint System indicator lamp in the instrument cluster
• Front passenger airbag OFF indicator lamp

A fault code is also stored in the Supplemental Restraint System control unit and an appropriate message appears in the display of the instrument cluster.

The supplemental restraint system control unit transmits the request to display a corresponding message via user interface CAN to the instrument cluster.

	Electric function schematic for deployment of supplemental restraint system		PE91.60-P-2055-97XBA
	Overview of system components for supplemental restraint system		GF91.60-P-9996FR