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GF91.60-P-0002G Supplemental Restraint System (SRS), Function




GF91.60-P-0002G Supplemental Restraint System (SRS), Function
MODEL 463.306 /336 /346 up to 31.5.12 as of model year 2011 /YoM 10
MODEL 463.202 /222 /236 /237 up to 31.5.12 as of model year 2009 /YoM 08
MODEL 463.247 /248 /249 /254 /270 /271 /303 /340 /341 up to 31.5.12 as of model year 2007

Function requirements
^ The supplemental restraint system (SRS) must be programmed to the vehicle (left or right-hand drive vehicle, equipment programming and configuration parameters)
^ Circuit 15R ON

SRS function
The SRS is comprised of the following subfunctions:
^ Front passenger seat occupied recognition sensor
^ Deploy SRS in the event of:
- Frontal impact,
- Rear-end collision or
- Side impact (only model 463.236/237/48/249/270/271/341/346)
^ System monitoring

The central control of the SRS takes place by the restraint systems control unit (N2/7).

The following restraint equipment can be triggered by the restraint systems control unit:
^ Driver emergency tensioning retractor unit
^ Front passenger emergency tensioning retractor unit
^ Left rear emergency tensioning retractor unit
^ Right rear emergency tensioning retractor unit
^ Driver airbag unit (two-stage)
^ Front passenger airbag unit
^ Left windowbag unit (only model 463.236/237/248/249/270/271/341/346)
^ Right windowbag unit (only model 463.236/237/248/249/270/271/341/346)

The following restraint equipment can be triggered by the NECK-PRO head restraint triggering device (N139):
^ Driver NECK-PRO head restraint solenoid (as of 1.9.10 in model 463.202/222/236/237/270/271/303/306/ 336/340/341/346)
^ Front passenger NECK-PRO head restraint solenoid (as of 1.9.10 in model 463.202/222/236/237/270/271/303/306/ 336/340/341/346)

In addition to deploying the restraint equipment, the following interventions are controlled by the restraint systems control unit in the event of a crash:
^ Engine shutoff
^ Door lock unlocking
^ Activation of hazard warning lamp function

System monitoring
The SRS monitors itself constantly and signals faults over the airbag indicator and warning lamp (A1e15) in the instrument cluster (A1) and over the automatic child seat recognition airbag OFF indicator lamp (N72/1e1) in the upper control panel control unit (N72/1) to the driver. All faults are stored in the nonvolatile memory of the restraint systems control unit. The airbag indicator and warning lamp and the automatic child seat recognition airbag OFF indicator lamp are switched off after t = 4 s following a successful self-test.

Capacitor
The restraint systems control unit provides power reserves for at least t = 1 s if the battery has been disconnected.

Seat belt lock system
Irrespective of the restraint systems control unit, the belt is prevented from extending in certain situations.