Head-on collision, function - GF91.60-P-2006RT

MODEL 251 up to Model Year 8

Course of emergency tensioning retractor activities in event of a moderately severe head-on collision for driver and passenger side

Fig 1: Course Of Emergency Tensioning Retractor Activities In Head-On Collision

Courtesy of MERCEDES-BENZ USA

Moderately severe head-on collision (1. triggering threshold)

If in the event of a moderately severe head-on collision the 1st. triggering threshold is exceeded, then only the seat belts are activated.

The restraint systems control unit (N2/7) registers over the driver-side frontal acceleration sensor (B48/1) or over the passenger-side frontal acceleration sensor (B48/2) a medium deceleration and activates the following squibs (this is contingent on a buckled seat belt):

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)

Course of front airbag triggering in event of a severe head-on collision for driver and passenger side

Fig 2: Course Of Front Airbag Triggering In Severe Head-On Collision

Courtesy of MERCEDES-BENZ USA

Severe head-on collision (2nd and 3rd triggering threshold)

If in the event of a severe head-on collision the 2nd. triggering threshold is exceeded, then the seat belts and front airbags are activated.

The restraint systems control unit registers severe deceleration over the driver-side or front passenger frontal acceleration sensor and activates the following squibs:

Driver and front passenger buckle ETR squibs
Left/right rear 2nd ETR [GUS] squib
Left/right 3rd row ETR [GUS] squib
driver airbag squib 1 (R12/13)
Passenger airbag squib 1 (R12/4)
Driver belt force limiter (R12/27)
Front passenger belt force limiter (R12/26)

If in the event of a severe head-on collision the 3rd. triggering threshold is exceeded, then the restraint systems control unit also activates the following squibs:

Driver airbag squib 2 (R12/14)
Passenger airbag squib 2 (R12/5)

Only with CODE (494) USA version

The left/right 2nd seat row does not have a seat belt query, as a consequence the left 2nd row ETR [GUS] squib and right 2nd seat row are always triggered.

WSS (Weight Sensing System)

The seat occupied and child seat recognition sensor is determined by the weight sensing system. A weight class is determined by measuring the weight on the front passenger seat and then sending it 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.

In the event of a collision and if the corresponding triggering threshold is exceeded than a signal is sent from the restraint systems control unit to the emergency call system control unit (N123/4) and an automatic emergency call is made.

Supplemental restraint system (SRS), function	Model 251.1 with code (494) USA version	GF91.60-P-0002RT
Supplemental restraint system (SRS), function	except code (494) USA version except code (498) Japanese version	GF91.60-P-0002RTE
Driver-side/front passenger frontal acceleration sensor component description		GF91.60-P-4033RT
WSS (Weight Sensing System) sensor, component description	Model 251.1 with CODE (494) USA version	GF91.60-P-4036RT
Driver airbag component description		GF91.60-P-4037RT
Front passenger airbag component description		GF91.60-P-4038RT
Front emergency tensioning retractor component description		GF91.60-P-4042RT
Rear emergency tensioning retractor component description		GF91.60-P-4043RT
Seat belt buckle switch component description		GF91.60-P-4045RT
Weight Sensing System (WSS), control unit, component description	Model 251.1 with code (494) USA version	GF91.60-P-4046RT
Restraint systems control unit, component description		GF91.60-P-4048RT