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

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

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

Supplemental restraint system, general
The supplemental restraint system is used for occupant protection.

The SRS comprises the following subfunctions:
^ System monitoring function sequence
^ Power reserve function sequence
^ Function sequence of additional functions in the event of a crash

Further partial functions are described in separate documents:
^ Passenger-side seat occupied recognition (without code (494) USA version)
^ Passenger-side seat occupied recognition (for code (494) USA version)
^ Trigger supplemental restraint system

System monitoring function sequence
The supplemental restraint system continuously monitors itself and signals faults to the driver via the airbag indicator and warning lamp (A1e15) in the instrument cluster (A1). The automatic child seat recognition airbag OFF indicator lamp (N72/1e1) is also switched on. All faults are stored in the nonvolatile memory of the restraint systems control unit (N2/7). The indicator lamps are switched off after t = 4 s following a successful self-test.

Power reserve function sequence
The restraint systems control unit provides a power reserve for the SRS for at least t = 150 ms if the battery has been disconnected. The following sensors are supplied with power for t = 30 ms:
- Drive sidebag sensor (A53)
- Front passenger sidebag sensor (A54)
- Driver-side frontal acceleration sensor (B48/1)
- Passenger-side frontal acceleration sensor (B48/2)

Function sequence of additional functions in the event of a crash
The additional functions in the event of a crash comprise the following subfunctions:
^ Function sequence for activation of hazard warning function
^ Function sequence for opening the central locking (CL [ZV])
^ Function sequence for shutting off the engine
^ Function sequence for automatic emergency call (for code (359) TELE AID emergency call system)

The interior illumination is switched on in the event of a crash. Also refer to the separate function description for the interior illumination.

Function sequence for activation of hazard warning function
After a crash event has occurred the hazard warning function is activated automatically via the exterior light components.

Also refer to the separate function description for the exterior lights.

The hazard warning function can be deactivated at any time by pressing the hazard warning system switch (N72/1s5).

Function sequence for opening the CL [ZV]
The CL [ZV] is unlocked automatically after a waiting time of t = 8 s to t = 11 s following the occurrence of a crash event. The crash signal is detected by the integrated crash sensor in the rear SAM control unit with fuse and relay module (N10/2).

The crash signal is transmitted via interior CAN. The following components are then actuated as follows:
- Left door central locking motor (M14/6) by the left door control unit (N69/1)
- Right door central locking motor (M14/5) by the right door control unit (N69/2)

Function sequence for shutting off the engine
The engine is shut off automatically after a crash event has occurred. The crash signal is transmitted by the restraint systems control unit via interior CAN to the central gateway control unit (N93). The central gateway control unit routes the signal on the engine compartment CAN to the ME-SFI [ME] control unit (N3/10). This then causes the engine to be shut off.

Function sequence for automatic emergency call
An emergency call is made automatically after a crash event has occurred. The crash signal is transmitted discretely by the restraint systems control unit to the emergency call system control unit (N123/4), which makes the automatic emergency call.

Also refer to the separate function description for the emergency call system.