Supplemental Restraint System Control Unit, Component Description - GF91.60-S-4080TRA

Model 447.6/7/8

Except Code XM7 (MOPF II)

Model 448.7/8

Shown on model 447.8

Fig 1: Supplemental Restraint System Control Unit Components Location - Model 447.6/7/8 Except Code XM7 (Shown On Model 447.8)

Courtesy of MERCEDES-BENZ USA

Location

The Supplemental Restraint System (SRS) control unit is located on the transmission tunnel.

Task

The Supplemental Restraint System (SRS) control unit has the following tasks:

Reading in of sensors and signals
Evaluation of input factors
Actuation of components

Reading in of sensors and signals

The input factors are read in via the following connections:

Direct line
Seat occupancy recognition LIN (LIN E2)
Chassis CAN (CAN E)

Direct line

The signals from the following sensors or switches are read in via direct lines:

Left B-pillar body acceleration sensor (B164) (with CODE SH8 (Window Airbag for driver, front passenger and rear)) (model 447.8)
Left B-pillar body acceleration sensor (with CODE SH9 (Window Airbag for driver and front passenger)) (model 448.7)
Left B-pillar body acceleration sensor (with CODE SH1 (Driver thorax/pelvis side airbag), with CODE SH2 (Front passenger thorax/pelvis side airbag), with CODE SH8 (Window airbag for driver, front passenger and rear passenger compartment), with CODE SH9 (Window airbag for driver and front passenger)) (model 447.6/7, 448.8)
Right B-pillar body acceleration sensor (B164/1) (with CODE SH8 (Window Airbag for driver, front passenger and rear)) (model 447.8)
Right B-pillar body acceleration sensor (with CODE SH9 (Window Airbag for driver and front passenger)) (model 448.7)
Right B-pillar body acceleration sensor (with CODE SH1 (Driver thorax/pelvis side airbag), with CODE SH2 (Front passenger thorax/pelvis side airbag), with CODE SH8 (Window airbag for driver, front passenger and rear passenger compartment), with CODE SH9 (Window airbag for driver and front passenger)) (model 447.6/7, 448.8)
Left C-pillar body acceleration sensor (B164/2) (with CODE SH8 (Window Airbag for driver, front passenger and rear)) (model 447.8, 448.8)
Left C-pillar body acceleration sensor (with CODE SH8 (Window Airbag for driver, front passenger and rear) and with CODE T19 (Left sliding door) or CODE T56 (Electrical actuation for left sliding door)) (model 447.6/7, 448.8)
Right C-pillar body acceleration sensor (B164/3) (with CODE SH8 (Window Airbag for driver, front passenger and rear))
Left sliding door pressure sensor (B165) (with CODE SH8 (Window Airbag for driver, front passenger and rear) and with CODE T19 (Left sliding door) or CODE T56 (Electrical actuation for left sliding door))
Right sliding door pressure sensor (B165/1) (with CODE SH8 (Window Airbag for driver, front passenger and rear))
Driver seat belt buckle restraint system switch (S68/1)
Front passenger seat belt buckle restraint system switch (S68/2)

Front passenger seat occupied recognition (B48/5) (without CODE SK5 (Automatic front passenger airbag shutoff)) (model 447.8, 448.8)
Front passenger seat occupied recognition (with CODE J55 (Seat belt warning system for front passenger seat) and without CODE SK5 (Automatic front passenger airbag shutoff)) (model 447.6/7, 448.7/8)

The Supplemental Restraint System (SRS) control unit also queries the status of Pyrosicherung A1 (F1fA1).

Seat occupied recognition LIN

The status of the weight sensing system (WSS) control unit (N110) (with CODE SK5 (Automatic front passenger airbag shutoff)) is sent via the seat occupancy LIN to the supplemental restraint system (SRS) control unit.

Chassis CAN

The following signal is read in via the chassis CAN:

Terminal status 15

The functions that use these signals are described in the individual function descriptions (see block diagram or function schematic).

Evaluation of input factors

The input factors that have been read in are evaluated by the integrated microprocessor and the relevant components are then actuated.

Actuation of components

The actuation of the components takes place via the following connections:

Direct line
Chassis CAN

Direct line

The following components are actuated via direct lines:

Pyrosicherung A1
Driver emergency tensioning retractor squib (R12/1) (without CODE JP1 (PRE-SAFE))
Front passenger emergency tensioning retractor squib (R12/2) (without CODE JP1 (PRE-SAFE))
Driver's airbag squib 1 (R12/7r1)
Driver's airbag squib 2 (R12/7r2)
Front passenger airbag squib 1 (R12/8r1)
Front passenger airbag squib 2 (R12/8r2)

Left front window airbag squib (R12/14)
Right front window airbag squib (R12/15)
Left center window airbag squib (R12/18) (with CODE SH8 (Window Airbag for driver, front passenger and rear))
Right center window airbag squib (R12/19) (with CODE SH8 (Window Airbag for driver, front passenger and rear))
Left rear window airbag squib (R12/22) (with CODE SH8 (Window Airbag for driver, front passenger and rear))
Right rear window airbag squib (R12/23) (with CODE SH8 (Window Airbag for driver, front passenger and rear))
Driver thorax-pelvis side airbag squib (R12/30) (model 447.8, 448.8)
Driver thorax/pelvis side airbag squib (with CODE SH1 (Driver thorax/pelvis side airbag)) (model 447.6/7, 448.8)
Front passenger thorax-pelvis side airbag squib (R12/31) (model 447.8, 448.8)
Front passenger thorax-pelvis side airbag squib (with CODE SH2 (Front passenger thorax-pelvis side airbag)) (model 447.6/7, 448.8)
Center front passenger emergency tensioning retractor squib (R12/34) (with CODE S23 (Two-seater front passenger seat)) (model 447.6/7)
Analog crash output to ME-SFI [ME] control unit (N3/34) (with engine 274)
Analog crash output to CDI control unit (N3/33) (with engine 651.9)
Analog crash output to CDI control unit (N3/36) (with engine 622.9)
Analog crash output to signal acquisition and actuation module (SAM) control unit (N10/1)

Chassis CAN

The following signals are transmitted via the chassis CAN:

Crash signal
Display fault message request
Display automatic child seat recognition request
Display via indicator lamp request

The functions that use these signals are described in the individual function descriptions (see block diagram or function schematic).

Wiring diagram for Supplemental Restraint System control unit	Model 447.8 except code XM7 (MOPF II)	PE91.60-S-2106-97VVA
	Model 447.6/7 except code XM7 (MOPF II)	PE91.60-S-2106-97VVC
Wiring diagram for Supplemental Restraint System (SRS) control unit	Model 448.8	PE91.60-S-2108-97VDA
	Model 448.7	PE91.60-S-2108-97VDB