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Home >> Mercedes Benz >> 2007 >> CL600 >> Repair and Diagnosis (Single Page) >> Accessories & Equipment >> Accessories Control Systems >> Battery, Collision Avoidance, Control Modules/Units, Displays, & Fuse/Relay Assignment -- Basic Knowledge -- Cl600 (216.376) >> Basic Knowledge >> RCP [HBF] control unit, component description - GF54.21-P-4510SX
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RCP [HBF] control unit, component description - GF54.21-P-4510SX

MODEL 221.0 /1 up to Model Year 8 

Location shown with code (406) Rear multicontour seat and with code (864) Rear entertainment system 

Fig 1: Identifying RCP [HBF] Control Unit
G07539305Courtesy of MERCEDES-BENZ USA

The RCP [HBF] control unit is located in the armrest between the rear seats.

Task on vehicles with code (864) Rear entertainment system 

Man Machine Interface (MMI) between the left rear display (A40/5), right rear display (A40/6) and the user.

The user's commands are recorded via the actuation of the following buttons integrated in the RCP [HBF] control unit and via the movement of the integral rear turn/push control (N72/2s8)

Actuation of the buttons and rotary push-button is converted into Controller Area Network (data bus/CAN bus) (CAN) messages by the electronics of the rear central operating unit and placed on the telematics CAN.

The CAN messages are read in directly by the left rear display and right rear display.

Task on vehicles with code (406) Rear multicontour seats 

The RCP [HBF] control unit takes over the task of an MMI between the multicontour seat system and the user.

The user's commands are recorded via the actuation of the following buttons integrated in the RCP [HBF] control unit and via the movement of the integral rear turn/push control

These actuations are converted into CAN messages by the RCP [HBF] control unit and placed on the Telematics CAN.

The COMAND control unit (A40/3) reads in these CAN messages and places them on the central CAN.

The central gateway control unit (N93) reads in these messages and passes them on to the rear seats control unit (N25/6) via the interior CAN.

Design shown with code (406) Rear multicontour seat and with code (864) Rear entertainment system 

Fig 2: Identifying RCP [HBF] Control Unit Components Location
G07539306Courtesy of MERCEDES-BENZ USA

Function 

Right screen button, with code (864) Rear entertainment system 

By pressing the right screen button the user can switch on the right rear display.

Left screen button, with code (864) Rear entertainment system 

By pressing the left screen button the user can switch on the left rear display.

Right "Back" button, with code (864) Rear entertainment system 

By briefly pressing the right "Back" button the current "Menu" or "Submenu" on the right rear display is closed and a change made to the preceding "Menu" or "Submenu". By pressing the right "Back" button for more than 3 s all the "submenus" on the right rear display are closed. The basic screen display of the previously selected "menu" appears in the right rear display.

Left "Back" button, with code (864) Rear entertainment system 

By briefly pressing the left "Back" button the current "Menu" or "Submenu" on the left rear display is closed and a change made to the preceding "Menu" or "Submenu". By pressing the left "Back" button for more than 3 s all the "submenus" on the left rear display are closed. The basic screen display of the previously selected menu appears in the left rear display.

Left seat selection button, with code (406) Rear multicontour seat 

By pressing the left seat selection button the user can select the left rear seat and at this adjust the "Seat setting" function or "Massage" function via the following buttons:

Right seat selection button, with code (406) Rear multicontour seat 

By pressing the right seat selection button the user can select the right rear seat and at this adjust the "Seat setting" function or "Massage" function via the following buttons:

Backrest side seat contour button, with code (406) Rear multicontour seat 

By pressing the backrest side seat contour button the user can change the volume and firmness of the two air cushions integrated in the left and right side of the backrest of the selected rear seat.

Lumbar support seat contour button, with code (406) Rear multicontour seat 

By pressing the lumbar support seat contour button the user can change the volume and firmness of the 3 air cushions integrated in the backrest of the selected rear seat.

Lumbar support height adjustment button, with code (406) Rear multicontour seat 

By pressing the lumbar support height adjustment button the user can change the position of the 3 air cushions integrated in the backrest of the selected rear seat.

Gentle massage function button, with code (406) Rear multicontour seat 

By pressing the gentle massage function button the user can select a gentle massage function of the selected rear seat. The volume and firmness of the air cushions integrated in the backrest are then varied.

Firm massage function button 

By pressing the firm massage function button the user can select a firmer massage function of the select rear seat. The volume and firmness of the air cushions integrated in the backrest are then varied.

Rear rotary push-button 

The rear rotary push-button is used to control the individual menus and submenus of the driver-relevant operating and information windows and the way in which video information from the following systems is shown on the left rear display or right rear display:

MOVING CURSOR IN LEFT REAR DISPLAY OR RIGHT REAR DISPLAY USING REAR ROTARY PUSH-BUTTON

Movement of rear rotary push-button Movement of cursor
Rotate clockwise The cursor moves to the right, or downward in vertical menus (exception: slider).
Turn counterclockwise The cursor moves to the left or upwards in vertical menus (exception: slider).
Push forward The cursor moves upward.
Push backward The cursor moves downward.
Push left The cursor moves to the left.
Push right The cursor moves to the right.
Press down vertically A selected menu or submenu is activated.

Step spacing 

The rotary movement of the turn/push control is recorded in the following 2 grids of different fineness:

The low-resolution spacing (12 steps per revolution) is mainly used for selecting menus. The high-resolution spacing (32 steps per revolution) is used for selecting and moving within long lists. The rear rotary push-button is locked at the end of a selection list, i.e. it is not possible to turn the rear rotary push-button further clockwise when the bottom of a selection list is reached.