Supplemental restraint system (SRS), function - GF91.60-P-0002M: Notes

MODELS 215, 220 as of 1.9.02 

System components 

The vehicle is equipped with the following airbag and emergency tensioning retractor units:

• Driver airbag, 1 stage with driver airbag squib (R12/3)
• Front passenger airbag (2-stage) with front passenger airbag squib 1

  (R12/4) and front passenger airbag squib 2 (R12/5)

• Left front sidebag with driver sidebag squib (R12/9)
• Right front sidebag with front passenger sidebag squib (R12/10)
• Left rear sidebag with left rear sidebag squib (R12/11)
• Right rear sidebag with right rear sidebag squib (R12/12)
• Left windowbag with left windowbag squib (R12/16),
• Right windowbag with right windowbag squib (R12/17)
• Driver emergency tensioning retractor with driver emergency tensioning retractor squib (R12/1) and driver belt force limiter (R12/27)
• Passenger emergency tensioning retractor with passenger emergency tensioning retractor squib (R12/2) and front passenger belt force limiter (R12/26)
• Left rear belt tensioning unit with rear left ETR squib (R12/6)
• Right rear emergency tensioning retractor unit with right rear ETR squib (R12/7)
• SRS left front seat belt buckle switch (S68/3)
• SRS right front seat belt buckle switch (S68/4)
• Drive buckle ETR squib (R46)
• Front passenger ETR squib (R46/1)

The airbag units bear the label "SRS Airbag".

Triggering characteristics shown on model 211.0 

The figures depict the deployment of various airbag and emergency tensioning retractor units in various types of accidents:

• In the event of rear-impact collisions as well as minor front-impact collisions, only the emergency tensioning retractors are deployed, with more severe head-on crashes the front airbags are also deployed.
• If the transverse acceleration threshold is exceeded in the event of a side impact, the corresponding side and windowbags are deployed.
• Under critical conditions (emergency braking, oversteering or understeering) the PRE-SAFE system (predictive occupant protection) is activated.

Function conditions 

• Circuit 15R ON
• Circuit 15 ON

The restraint systems control unit (N2/7) senses crash type and severity and deploys precisely those airbag and ETR units necessary to provide optimum passenger protection.

Digital crash output 

Actuated when one of 5 activation criteria is met, in order to notify the control units involved of the type of crash by means of a crash telegram.

The digital crash output can be programmed as equipment. A test of the equipment variant and cable is stored.

This test is performed as soon as "Circuit 15R ON" and t ≈ 2 sec.

Seat occupied recognition sensor 

In deploying the systems, the control unit also takes into account the data received from the passenger seat occupied and child seat recognition sensor (B48), as well as the switching states of the seat belt buckle switches.

The front passenger seat occupied and child seat recognition sensor (B48) prevents the airbag and emergency tensioning retractor units on the front passenger side from being deployed under certain conditions.

The automatic child seat recognition function and the deactivation of the front passenger airbag by the automatic child seat recognition is indicated by the automatic child seat recognition airbag OFF indicator lamp (E16).

Diagnosis 

Diagnosis takes place using STAR DIAGNOSIS.

System monitoring 

Malfunctions in the system are indicated by the airbag indicator and warning lamp (A1e15) and the multifunction display (A1p13) in the instrument cluster (A1).

For this purpose, the instrument cluster (A1) receives the corresponding message from the restraint systems control unit (N2/7) via the interior CAN.

The driver and front passenger seat belt warnings are being changed as of 28.10.03. If the driver and front passenger seats are detected as being occupied and the seat belt switches indicate "Seat belts not applied" a beeping noise will be heard in the future. The beeping starts from a speed of 25 km/h and remains active for 95 sec.

Working on the restraint systems control unit (N2/7) 

The restraint systems control unit (N2/7) has an integrated roll sensor. The transmitter key (A8/1) must always be removed when working on or with the restraint systems control unit (N2/7), otherwise there is a risk of accidental airbag triggering. The relevant safety there is a risk of accidental airbag triggering. The relevant safety information in the work instructions must be complied with.

Disposal 

When handling and disposing of airbag and emergency tensioning retractor units, the corresponding safety and disposal information in the work instructions must be fully observed.

	Supplemental Restraint System (SRS) Deployment Logic		GF91.60-P-0002-08M
	Supplemental restraint system (SRS), block diagram		GF91.60-P-0002-03M
	Seat belt wearing convenience, function	Models 215, 220	GF91.40-P-2000S
	Head-On Collision - Function		GF91.60-P-2006M
	Predictive occupant protection function		GF91.60-P-2010B