Rear end collision, function - GF91.60-P-2004RT
MODEL 251 up to Model Year 8
Sequence of emergency tensioning retractor activities and the NECK-PRO head restraints in the event of a rear end collision for the driver and passenger-sides
Course of emergency tensioning retractor activities in event of a rear end collision for driver and passenger side
If the restraint systems control unit (N2/7) registers high vehicle acceleration and deceleration as a consequence of a rear end collision, a trigger pulse is issued to the following components:
- Drive buckle ETR squib (R46)
- Front passenger ETR squib (R46/1)
- Left 2nd row ETR [GUS] squib (R12/6)
- Right 2nd row ETR [GUS] squib (R12/7)
- Left 3rd row ETR [GUS] squib (R12/35)
- Right 3rd row ETR [GUS] squib (R12/36)
If the seat belt on the driver or passenger side is not engaged in the seat belt buckle, then this fact is registered by the restraint systems control unit.
Registration is performed via the driver seat belt buckle and seat belt warning switch (S68/1) or via the front passenger seat belt buckle and seat belt warning switch (S68/2) and does not trigger the corresponding driver ETR [GUS] squib or the front passenger ETR [GUS] squib.
Belt buckle check up to production period 31.05.06
If the driver seat belt buckle and seat belt warning switch, front passenger seat belt buckle and seat belt warning switch, left rear seat belt buckle switch (S68/11) and right rear seat belt buckle switch (S68/12), left 3rd seat row seat belt buckle switch (S68/16) and right 3rd seat row seat belt buckle switch (S68/17) signal that a seat belt has not been engaged, then the respective emergency tensioning retractors are not triggered by the restraint systems control unit.
Belt buckle check as of production period 01.06.06
If the driver-side seat belt buckle and seat belt reminder warning switch, the passenger-side seat belt buckle and seat belt reminder warning switch signal that a seat belt is not buckled, the particular emergency tensioning retractors are not triggered by the restraint systems control unit.
The seat belts in the 2nd and 3rd seat rows are not checked. The emergency tensioning retractors for the 2nd and 3rd seat rows are triggered if the latch plate is not inserted.
Only for code 494 USA version
There is no seat belt buckle query for the left and right rear seats, as a consequence the left rear and right rear ETR squibs are always triggered in the event of a collision.
In the event of a collision and if the corresponding triggering threshold is exceeded, then a signal is additionally sent from the restraint systems control unit to the emergency call system control unit (N123/4) and an automatic emergency call is made.
WSS (Weight Sensing System)
The seat occupied and child seat recognition is determined by the weight sensing system (WSS). A weight measurement in the front passenger seat enables a weight class to be determined and this is sent to the restraint systems control unit. The restraint systems control unit uses the weight class to determine whether a suppression, a 1-stage or 2-stage triggering of the front passenger airbag is necessary.
| Supplemental restraint system (SRS), function | Model 251.1 with code 494 USA version | GF91.60-P-0002RT | |
| Model 251 except code 494 USA version Model 251 except code 498 Japanese version |
GF91.60-P-0002RTE | ||
| Front emergency tensioning retractor component description | GF91.60-P-4042RT | ||
| Rear emergency tensioning retractor component description | GF91.60-P-4043RT | ||
| Reversible belt emergency tensioning retractor, component description | GF91.60-P-4050RT | ||
| Driver/passenger-side NECK-PRO head restraints | GF91.60-P-4053GZ | ||
| Seat belt buckle switch, component description | GF91.60-P-4045RT | ||
| 3rd seat row emergency tensioning retractor, component description | GF91.60-P-4063GY | ||
| Restraint systems control unit, component description | GF91.60-P-4048RT |