Component Description For Rear Sam Control Unit - GF54.21-P-7030FG

Model 213 up to model year 2021 

Location 

The rear SAM control unit is on the right in the trunk behind the cover.

Tasks 

Depending on the function sequence, the rear SAM control unit supplies voltage to various systems and control units 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/liftgate lock main lock switch (A85/5s1)
• Trunk lid/liftgate lock safety catch switch (A85/5s2) (with code 883 (Power closing))
• Tank cap central locking actuator (M14/10)
• Reverse switch for trunk lid/liftgate lock element (M14/31) (model 213.2 with code 890 (EASY-PACK liftgate))
• Rear window roller sun blind motor Hall sensor (M24) (model 213.0/1 with code 540 (Electric roller sun blind for rear window))
• Rear camera cover motor switch (M35/2s1) (with code 218 (Reversing camera) or code 235 (Parking Pilot with PARKTRONIC) or code P44 (Parking Package))
• Left load compartment cover actuator motor Hall sensor (M50/1) (model 213.2 with code 541 (Twin roller blinds (incl. partition net)))
• Right load compartment cover actuator motor Hall sensor (M50/2) (model 213.2 with code 541 (Twin roller blinds (incl. partition net)))
• Electronic Stability Program control unit (N30/4) (circuit 54)
• Right rear brake wear sensor (S10/4)
• Left rear seat backrest inclination switch (S54/5) (model 213.0 with code 287 (Folding rear seat backrests), model 213.2)
• Right rear seat backrest inclination switch (S54/6) (model 213.0 with code 287 (Folding rear seat backrests), model 213.2)
• Rear left backrest lock switch (S54/7) (model 213.0 with code 287 (Folding rear seat backrests), model 213.2)
• Rear right backrest lock switch (S54/8) (model 213.0 with code 287 (Folding rear seat backrests), model 213.2)
• Left trunk rear backrest release button (S54/9) (model 213.2)
• Right trunk rear backrest release button (S54/10) (model 213.2)
• Left rear backrest release button (S54/11) (model 213.2)
• Right rear backrest release button (S54/12) (model 213.2)
• Trunk lid/liftgate control button (S62/26) (model 213.0/1 with code 881 (Remote trunk closing), model 213.2 with code 890 (EASY-PACK liftgate))
• Left rear seat belt buckle switch (S68/11)
• Right rear belt buckle switch (S68/12)
• Center rear seat belt buckle switch (S68/14)
• Left 3rd seat row seat belt buckle switch (S68/16) (model 213.2 with code 844 (Folding bench seat in load compartment))
• Right 3rd seat row seat belt buckle switch (S68/17) (model 213.2 with code 844 (Folding bench seat in load compartment))
• Load compartment cover limit switch (S69/14) (model 213.2 with code 541 (Twin roller blinds (incl. partition net)))
• Trunk lid/liftgate external operation switch (S88/8)
• Trunk lid emergency opening switch (S88/10) (model 213.0 with code 460 (Canada version) or code 494 (USA version))

Interior CAN 

The signals are read in by the rear SAM control unit via the interior CAN.

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

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 rear seat heaters (with code 872 (Rear seat heating), model 213.1 with code 402 (Rear comfort seats, including seat heating and seat ventilation) or code 903 (Seat heating Plus for rear passenger compartment outer seats))
• Front seat ventilation (with code 401 (Seat climate control for driver and front passenger))
• Rear seat ventilation (model 213.1 with code 402 (Rear comfort seats, including seat heating and seat ventilation))
• Trunk lid/liftgate power closing (with code 883 (Power closing))

Actuation of components 

The following components are actuated via direct lines:

• Trunk lid/liftgate lock motor (A85/5m1)
• Left rear lamp unit (E3)
• Right rear lamp unit (E4)
• Trunk lamp (E18/1) (model 213.0/1)
• Right trunk lamp (E18/4) (model 213.2)
• Left trunk lamp (E18/5) (model 213.2)
• Left license plate lamp (E19/1)
• Right license plate lamp (E19/2)
• Center brake lamp (E21)
• Left trunk lid/liftgate ambient lamp and warning lamp (E40/2)
• Right trunk lid/liftgate ambient lamp and warning lamp (E40/3) (model 213.2)
• Seat belt comfort-fit function solenoid, left rear seat (K18/6) (model 213.0 with code P36 (Rear PRE-SAFE® package))
• Seat belt comfort-fit function solenoid, right rear seat (K18/7) (model 213.0 with code P36 (Rear PRE-SAFE® package))
• Liftgate wiper motor (M6/4) (model 213.2)
• Tank cap central locking actuator
• Trunk lid/liftgate lock element (model 213.0/1 with code 881 (Remote trunk closing), model 213.2 with code 890 (EASY-PACK liftgate))
• Rear window roller sun blind motor (model 213.0/1 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) or code P44 (Parking Package))
• Left load compartment cover actuator motor (model 213.2 with code 541 (Twin roller blinds (incl. partition net)))
• Right load compartment cover actuator motor (model 213.2 with code 541 (Twin roller blinds (incl. partition net)))
• Left rear head restraint release actuator (M53/12) (model 213.2)
• Right rear head restraint release actuator (M53/14) (model 213.2)
• Left rear backrest release actuator (M53/15) (model 213.2)
• Right rear backrest release actuator (M53/16) (model 213.2)
• 3rd seat row liftgate unlocking switch (S15/6) (model 213.2 with code 844 (Folding bench seat in load compartment))
• Load compartment rail lighting (in coordination) (model 213.2)
• 48 V on-board electrical system battery (G1/3) (with code B01 (48V technology))

The rear SAM control unit additionally supplies voltage to the comfort switch and controls illumination, switch illumination (circuit 58d) and ambiance illumination (with code 877 (Ambiance illumination)).

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.

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

Wiring diagram for rear signal acquisition and actuation module (SAM) control unit

PE54.21-P-2103-97DBA