GF91.60-P-2001CA Deploy Supplemental Restraint System, Function

GF91.60-P-2001CA Deploy Supplemental Restraint System, Function

Function requirements, general
^ Circuit 15R ON

The electronic ignition control unit (N73) sends the status of circuit 15R via chassis CAN (CAN E) to the supplemental restraint system control unit (N2/10).

Deploying supplemental restraint system, general
The supplemental restraint system (SRS) constantly monitors the occupation status of the front passenger seat, the status of the front seat belts (buckled or not buckled) and uses this information to adjust its deployment.

The triggering of the supplemental restraint system is made up of the following partial functions:
^ Function sequence for detecting occupied status of front passenger seat
^ Function sequence for detecting status of front seat belts
^ Function sequence for impact detection
^ Function sequence for frontal impact
^ Function sequence for side impact
^ Function sequence for rear end collision
^ Function sequence for rollover
^ Function sequence for additional functions in the event of a crash

Function sequence for detecting occupied status of front passenger seat
The supplemental restraint system control unit receives the corresponding information from the following components:
- Front passenger seat occupied recognition (B41/1) (without code (U18) Automatic child seat recognition (ACSR) without code (494) USA version)
- Front passenger seat occupied recognition and ACSR (B48) (with code (U18) automatic child seat recognition (ACSR))
- WSS (Weight Sensing System) control unit (N110) (with code (494) USA version)

Without code (U18) Automatic child seat recognition (ACSR [AKSE]) the status of the seat occupied recognition does not influence the deployment behavior of the supplemental restraint system.

Function sequence for detecting status of front seat belts
The driver seat belt buckle restraint system switch (S68/3) or the front passenger seat belt buckle restraint system switch (S68/4) is actuated by the belt latch which is inserted into the seat belt buckle.

The status of the supplemental restraint system is read in directly by the supplement restraint system control unit.

The status of the rear seat belts does not have any influence on the deployment behavior of the SRS.

Function sequence for impact detection
The supplement restraint system control unit determines the acceleration acting on the vehicle with the aid of the following sensors:
- Integrated sensor
- Left sidebag sensor (A53)
- Right sidebag sensor (A54)
- Left frontal acceleration sensor (B48/1)
- Right frontal acceleration sensor (B48/2)
- Left front door pressure sensor (B48/7)
- Right front door pressure sensor (B48/8)

With the aid of this sensor system, the SRS is able to distinguish between the following types of impacts:
- Head-on collision
- Side-on collision
- Rear end collision
- Roll-over

Function sequence for frontal impact
A frontal impact is detected by the supplemental restraint system control unit via the signals from the following components:
- Integrated sensor
- Left frontal acceleration sensor
- Right frontal acceleration sensor

The restraint equipment is deployed depending on the severity of the impact, the occupation of the front passenger seat, and the status of the front seat belts.

The following squibs can be ignited (at most):
- Driver ETR [GUS] squib (R12/1)
- Passenger ETR squib (R12/2)
- Front passenger airbag squib 1 (R12/4)
- Front passenger airbag squib 2 (R12/5)
- Left rear emergency tensioning retractor squib (R12/6)
- Right rear emergency tensioning retractor squib (R12/7)
- Driver airbag squib 1 (R12/13)
- Driver airbag squib 2 (R12/14)
- Driver kneebag squib (R12/25)

The following situations are taken into account:
- Occupied state of the front passenger seat:
The supplemental restraint system control unit uses the current occupancy to decide whether to suppress the front passenger airbag unit or to use 1-stage or 2-stage deployment.

- Driver seat belt buckle status:
If the driver seat belt buckle restraint system switch detects that a belt latch is not inserted into the seat belt buckle, the driver airbag unit with advanced ignition timing is triggered instead of the driver emergency tensioning retractor unit.

- Front passenger seat belt buckle status:
If the front passenger seat belt buckle restraint system switch detects that a belt latch is not inserted into the seat belt buckle, the front passenger airbag unit with advanced ignition timing is triggered instead of the front passenger emergency tensioning retractor unit.

This only applies, however, if the front passenger seat is known to be occupied. If not occupied, then neither the emergency tensioning retractor nor the front passenger airbag unit are deployed.

Function sequence for side impact
A side impact is detected by the supplemental restraint system control unit via the signals from the following components:
- Integrated sensor
- Left sidebag sensor
- Right sidebag sensor
- Left front door pressure sensor
- Right front door pressure sensor

The activation of the restraint equipment takes place depending on the severity of the impact and occupation of the front passenger seat.

The following squibs can be ignited (at most):
- Driver ETR [GUS] squib
- Front passenger ETR [GUS] squib
- Left rear emergency tensioning retractor squib
- Right rear emergency tensioning retractor squib
- Driver sidebag squib (R12/9) (model 207.3)
- Front passenger sidebag squib (R12/10) (model 207.3)
- Left rear sidebag squib (R12/11) (with code (293) Left and right rear sidebag)
- Right rear sidebag squib (R12/12) (with code (293) Left and right rear sidebag)
- Left windowbag squib (R12/22) (model 207.3)
- Right windowbag squib (R12/23) (model 207.3)
- Left Head/Thorax bag squib (R12/39) (model 207.4)
- Right Head/Thorax bag squib (R12/40) (model 207.4)
- Driver pelvis airbag squib (R12/41) (with code (291) PELVIS AIRBAG (PELVISBAG))
- Front passenger pelvis airbag squib (R12/42) 5G(with code (291) PELVIS AIRBAG (PELVISBAG))

The following state is taken into consideration:
- The supplemental restraint system control unit makes a decision about triggering the front passenger sidebag unit based on the current occupation of the front passenger seat.

Function sequence for rear end collision
A rear-end collision is detected by the supplemental restraint system control unit via the signals from the following components:
- Integrated sensor
- Left sidebag sensor
- Right sidebag sensor
- Left frontal acceleration sensor
- Right frontal acceleration sensor

The activation of the restraint equipment takes place depending on the severity of the impact and the status of the front seat belts.

The following squibs can be ignited (at most):
- Driver ETR [GUS] squib
- Front passenger ETR [GUS] squib
- Left rear emergency tensioning retractor squib
- Right rear emergency tensioning retractor squib

The following components are actuated additionally:
- Driver seat NECK-PRO head restraint solenoid (Y24/12)
- Front passenger seat NECK-PRO head restraint solenoid (Y24/13)

The following situations are taken into account:
- Driver seat belt buckle status:
If the driver seat belt buckle restraint systems switch detects that a belt latch is not inserted into the seat belt buckle, the driver emergency tensioning retractor unit is not triggered.

- Front passenger seat belt buckle status:
If the front passenger seat belt buckle restraint systems switch detects that a belt latch is not inserted into the seat belt buckle, the front passenger emergency tensioning retractor unit is not triggered.

Function sequence for rollover
A rollover is detected by the supplemental restraint system control unit via the integrated sensor. Only one roll-over around the longitudinal vehicle axis can be detected.

The following squibs can be ignited (at most):
- Driver ETR [GUS] squib
- Front passenger ETR [GUS] squib
- Left rear emergency tensioning retractor squib
- Right rear emergency tensioning retractor squib

The following situations are taken into account:
- Driver seat belt buckle status:
If the driver seat belt buckle restraint systems switch detects that a belt latch is not inserted into the seat belt buckle, the driver emergency tensioning retractor unit is not triggered.

- Front passenger seat belt buckle status:
If the front passenger seat belt buckle restraint systems switch detects that a belt latch is not inserted into the seat belt buckle, the front passenger emergency tensioning retractor unit is not triggered.

With model 207.4, the roll bars are triggered in the event of a rollover. To do so, the left roll bar airbag squib (R12/45) and the right roll bar airbag squib (R12/46) are actuated by the supplemental restraint system control unit. Within a split second the rear head restraints in which the roll bars are integrated are extended.

Function sequence for 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 opening the side windows
^ Function sequence for shutting off the engine
^ Function sequence for automatic emergency call (with code (359) TELE AID emergency call system)
^ Function sequence for activating crash-active exit aid (with code (275) Memory package (driver seat, steering column, mirror))

Function sequence for activation of hazard warning function
When an airbag is deployed, the supplemental restraint system control unit sends a corresponding signal via chassis CAN to the front SAM control unit with fuse and relay module 8 (N10/1). The front SAM control unit starts the hazard warning flasher function by outputting the flasher frequency via interior CAN (CAN B) and actuates the following lamps directly:
- Left front turn signal lamp (E1e5)
- Right front turn signal lights (E2e5)

The lamps are actuated as follows:
- Left outside mirror turn signal lamp (N69/1) by the left front door control (E6/5)
- Right outside mirror turn signal lamp (N69/2) by the right front door control unit (E6/6)
- Left rear turn signal lamp and right rear turn signal (N10/2) by the right front door control unit E3e1 E4e1

The hazard warning function can be deactivated at any time by pressing the hazard warning flasher switch (S6/1s1).

Function sequence for opening the central locking
The central locking is unlocked automatically after a crash event has occurred. The crash signal is sent by the supplemental restraint system control unit over the chassis CAN to the front SAM control unit. This sends the crash signal via interior CAN.

The following central locking motors are then actuated:
- Left front door control locking motor by left front door control unit (A85m1)
- Right front door central locking motor by right front door control unit (A85/1m1)

The central locking is unlocked after a waiting time of t = 8 to 11 s.

Function sequence for opening the side windows
The side windows are opened automatically after a crash event has occurred. The crash signal is sent by the supplemental restraint system control unit over the chassis CAN to the front SAM control unit. This sends the crash signal via interior CAN. The following power window motors are then actuated:
- Left front door power window motor by left front door control unit (M10/3)
- Right front door power window motor by right front door control unit (M10/4)
- from rear control unit (N22/6) for the left rear power window motor (M10/5) and the right rear power window motor (M10/6)

Function sequence for shutting off the engine
The engine is shut off automatically after a crash event has occurred. The crash signal is sent by the supplemental restraint system control unit over the chassis CAN to the CDI control unit (N3/9) (for diesel engine) or to the ME-SFI [ME] control unit (N3/10) (for gasoline engine). This then causes the engine to be shut off.

Function sequence for automatic emergency call (with code (359) TELE AID emergency call system)
An emergency call is made automatically after a crash event has occurred. The crash signal is sent by the supplemental restraint system control unit over the chassis CAN to the front SAM control unit. This then sends the crash signal over the diagnostic CAN (CAN D) to the emergency call system control unit (N123/4), which triggers an automatic emergency call.

The crash signal is also sent over a direct line from the supplemental restraint system control unit to the emergency call system control unit.

Function sequence for activating crash-active exit aid (with code (275) Memory package (driver seat, steering column, mirror))
After a crash, the steering column is automatically moved upward during the following actions:
- Driver door opened
- Removing transmitter key (A8/1) from electronic ignition lock control unit

The driver seat control unit (N32/1) receives the following information via the interior CAN:
- Crash signal from front SAM control unit (the front SAM control unit receives the crash signals from the supplemental restraint system control unit via the chassis CAN)
- Status of driver door from left front door control unit
- Circuit status of clamp 15C OFF from electronic ignition lock control unit

After receiving the information, the driver seat control unit actuates the steering column adjustment up/down motor (M20/2) to adjust the steering column upward.