Left Front Door Control Unit, Component Description - GF72.29-P-6001FR

Model 257, 290 

up to model year 2021 

Shown on model 257 

Location 

The left front door control unit is located on the door module behind the door lining.

Task 

The left front door control unit has the following tasks:

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

Reading in of sensors and signals 

The input factors are read in via the following connections:

• Direct line 
• Left front door LIN (LIN B5) 
• Interior CAN (CAN B) 

Direct line 

The signals from the following components are read via direct lines:

• Left front door external operation microswitch (A85s1) (with CODE 883 (Power closing))
• Left front door main catch microswitch (A85s2)
• Left front door inside door handle microswitch (A85s3) (with CODE 883 (Power closing))
• Left front door external operation microswitch (A85s4) (with CODE 883 (Power closing))
• Left front door power closing microswitch actuator motor (M14/21s1) (with CODE 883 (Power closing))
• Vertical inclination adjustment potentiometer (M21/1r2) (with code P49 (Mirror package))
• Horizontal inclination adjustment potentiometer (M21/1r3) (with code P49 (Mirror package))
• Left front door armrest heating element temperature sensor (R16/5b1) (with code 906 (Front armrest heater))
• Trunk lid release button (S15/1) (left-hand drive vehicle, model 257 except code 881 (Remote trunk closing))
• Driver trunk lid/liftgate control button (S15/3) (left-hand drive vehicle, model 257 with code 881 (Remote trunk closing), model 290)
• Front passenger side power window switch (S21/2) (right-hand drive vehicle)
• Left front door central locking inside door handle switch (S85/5)
• Driver's door fully electric trailer hitch switch (S142/3) (left-hand drive vehicle with code 550 (Trailer hitch))

Left front door LIN 

The signals for the following components are read in via the left front door LIN:

• Driver's side power window and outside mirror adjustment switch group (S20) (left-hand drive vehicle):
  • Left front power window switch (S20s1)
  • Right front power window switch (S20s2)
  • Left rear power window switch (S20s3)
  • Right rear power window switch (S20s4)
  • Rear side window child safety lock switch (S20s5)
  • Outside mirror fold-in/out switch (S20s6) (with CODE P49 (Mirror package))
  • Left outside mirror adjustment switch (S20s7)
  • Right outside mirror adjustment switch (S20s8)
  • Outside mirror adjustment switch (S20s9)
• Left front seat adjustment switch group (S22) (with code 278 (Fully electric front seats) or code 275 (Memory Package)):
  • Left front head restraint adjustment switch (S22s1) (with CODE 275 (Memory package))
  • Left front seat inclination adjustment switch (S22s2)
  • Left front seat fore/aft adjustment switch (S22s3)
  • Left front seat height adjustment switch (S22s4)
  • Left front seat backrest adjustment switch (S22s5)
  • Left front seat cushion length adjustment switch (S22s6) (with CODE 275 (Memory package))
  • Left front memory function switch (S22s7) (with CODE 275 (Memory package))
  • Left front memory 1 switch (S22s8) (with CODE 275 (Memory package))
  • Left front memory 2 switch (S22s9) (with CODE 275 (Memory package))
  • Left front memory 3 switch (S22s10) (with CODE 275 (Memory package))
• Left front seat climate control switch group (S51/1) (with code 401 (Seat climate control for driver and passenger), code 873 (Seat heater for driver and passenger) or code 902 (Seat heater plus for driver and passenger)):
  • Left front seat heater switch (S51/1 s2)
  • Left front seat ventilation switch (S51/1s3) (with CODE 401 (Seat climate control for driver and front passenger))

Interior CAN 

The left front door control unit reads in the following signals via the interior CAN:

• Terminal status of terminal 15
• 'Reverse gear engaged' signal
• Central locking system unlocking/locking request
• PRE-SAFE® adjustment request
• Move to memory position request (with CODE 275 (Memory package))
• Convenience feature request
• Crash signal

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 following components are actuated via direct lines:

• Left front door central locking motor (A85m1)
• Left front door additional door lock actuator motor (with code (A85m4) with code 885 Extended theft protection))
• Left front door exit lamp (E17/3)
• Left front door outer door handle illumination (E17/7) (with CODE 889 (KEYLESS-GO))
• Left front door warning lamp (E17/19)
• Left front door pocket lighting (E23/1) (with code 891 (Premium ambient lighting))
• Left front door power window motor (M10/3)
• Left front door power closing actuator motor (M14/21) (with CODE 883 (Power closing))
• Left outside mirror (M21/1):
  • Left outside mirror turn signal lamp (E6/5)
  • Left outside mirror ambient lamp (M21/1e1)
  • Left Blind Spot Assist warning display (M21/1e2) (with code 233 (Distance Pilot DISTRONIC with Steering Pilot) or code 234 (Blind Spot Assist))
  • Mirror dimming (M21/1h1) (with CODE P49 (Mirror package))
  • Vertical inclination adjustment actuator motor (M21/1m1)
  • Horizontal inclination adjustment actuator motor (M21/1m2)
  • Outside mirror fold in/out electric motor (M21/1m3) (with CODE P49 (Mirror package))
  • Mirror heater (M21/1 r1)
• Left front door armrest heating element (R16/5) (with code 906 (Front armrest heater))
• Status LED in driver's door fully electric trailer hitch switch (with code 550 (Trailer hitch))

The left front door control unit supplies the switch illumination (circuit 58d) with power.

The left front door control unit supplies the following component parts of the ambient lighting (with code 891 (Premium ambient lighting)) with power:

• Left front door ambiance illumination (E17/43)
• Left front door door handle ambient lighting (E17/55)

Transmitting signals 

The left front door control unit sends signals over the following connections:

• Left front door LIN 
• Interior CAN 

Left front door LIN 

The left front door control unit transmits the following signals via the left front door LIN:

• Left or right outside mirror adjustment switch selection status indication
• Rear side window child safety lock status indication
• Seat heater status (with code 401 (Seat climate control for driver and passenger), code 873 (Seat heater for driver and passenger) or code 902 (Seat heater plus for driver and passenger))
• Seat ventilation status (with CODE 401 (Seat climate control for driver and front passenger))

Interior CAN 

The left front door control unit reads in the following signals via the interior CAN:

• Door status (open/closed)
• Adjust right outside mirror request (left-hand drive vehicle)
• Open/close power window switch request (left-hand drive vehicle)
• Convenience feature mode (left-hand drive vehicle with code 889 (KEYLESS-GO))
• Convenience feature direction (left-hand drive vehicle with code 889 (KEYLESS-GO))
• Seat ventilation request (with code 401 (Seat climate control for driver and front passenger))
• Seat heater request (with code 401 (Seat climate control for driver and passenger), code 873 (Seat heater for driver and passenger) or code 902 (Seat heater plus for driver and passenger))
• Seat adjustment request (with code 278 (Fully electric front seats) or code 275 (Memory Package))
• Unlock trunk request (left-hand drive vehicle)

Electrical wiring diagram for left front door control unit

PE72.29-P-2101-97XBA