Component Description For Rear SAM Control Unit - GF54.21-P-7030FH
Model 238
Up To Model Year 2021
Shown On Model 238.3
Location
The rear SAM control unit is located at the right in the trunk recess under the cover.
Tasks
Depending on the function sequence the rear SAM control unit supplies various systems and control units with voltage via limit switches. In addition, the rear SAM control unit has the following tasks:
- Reading in of sensors and signals
- Evaluation of input factors
- Controlling functions
- Actuation of components
- Switching of relays
- Sending signals
Reading in of sensors and signals
The input factors are read in via the following connections:
- Direct line
- Interior CAN (CAN B)
Direct line
The signals from the following components are read via direct lines:
- Trunk lid lock main catch switch (A85/5s1)
- Tank cap central locking actuator (M14/10)
- Rear camera cover motor switch (M35/2s1) (with code 218 (Reversing camera) or code 235 (Parking Pilot with PARKTRONIC))
- Electronic Stability Program control unit (N30/4) (circuit 54)
- Right rear brake wear sensor (S10/4)
- Left rear backrest inclination switch (S54/5)
- Right rear backrest inclination switch (S54/6)
- Left rear backrest lock switch (S54/7) (Model 238.3)
- Right rear backrest lock switch (S54/8) (Model 238.3)
- Left trunk rear seat backrest release button (S54/9) (Model 238.4)
- Right trunk rear seat backrest release button (S54/10) (Model 238.4)
- Trunk lid control button (S62/26) (with code 881 (Remote trunk closing))
- Left rear seat belt buckle switch (S68/11)
- Center rear seat belt buckle switch (S68/14)
- Trunk lid external operation switch (S88/8)
- Trunk lid emergency opening switch (S88/10) (with code 494 (USA version))
Interior CAN
The signals are read in by the rear SAM control unit via the interior CAN.
Evaluation of input factors
The input factors are evaluated by the microprocessor and the corresponding components are actuated.
Controlling functions
The rear SAM control unit controls the following functions:
- Central locking
- Front seat heater (with code 401 (Seat climate control for driver and front passenger), code 873 (Seat heater for driver and front passenger) or code 902 (Seat heater Plus for driver and front passenger))
- Rear seat heater (with code 872 (Seat heater in rear))
- Front seat ventilation (with code 401 (Seat climate control for driver and front passenger))
- Trunk lid power closing (with code 883 (Power closing))
Actuation of components
The following components are actuated via direct lines:
- Trunk lid lock motor (A85/5m1)
- Left rear lamp unit (E3)
- Inner left rear lamp unit (E3/1)
- Right rear lamp unit (E4)
- Inner right rear lamp unit (E4/1)
- Left rear footwell lamp (E17/17)
- Right rear footwell lamp (E17/18)
- Trunk lid warning lamp (E17/27) (Model 238.3)
- Trunk lamp (E18/1) (Model 238.3)
- Left trunk lamp (E18/5) (Model 238.4)
- Right trunk lamp (E18/4) (Model 238.4)
- Left license plate lamp (E19/1)
- Right license plate lamp (E19/2)
- Center brake lamp (E21)
- Trunk lid ambient lamp (E40) (Model 238.3)
- Left trunk lid/liftgate ambient lamp and warning lamp (E40/2) (Model 238.4)
- Tank cap central locking actuator
- Central locking system stowage compartment actuator motor (M14/19) (Model 238.4 with code 882 (Interior protection and tow-away protection))
- Trunk lid lock element (M14/31) (with code 881 (Remote trunk closing))
- Rear window roller sun blind motor (with code 540 (Electric roller sun blind for rear window))
- Rear camera cover motor (M35/2) (with code 218 (Reversing camera) or code 235 (Parking Pilot with PARKTRONIC))
- Left backrest release/backrest inclination microswitch (S91/6)
- Right backrest release/backrest inclination microswitch (S92/6)
- Left rear backrest release actuator (M53/15)
- Right rear backrest release actuator (M53/16)
- Switch illumination power supply (circuit 58d)
Switching of relays
The following relays are switched by the rear SAM control unit:
- Rear window heater relay (K40/5kT)
- 2nd seat row cup holder and sockets relay (K40/5kU)
- 1st seat row/trunk refrigerator box and sockets relay (K40/5kX)
Sending signals
The signals are sent by the rear SAM control unit over the interior CAN.
| Wiring diagram for rear signal acquisition and actuation module (SAM) control unit | PE54.21-P-2103-97DCA |