Upper control panel control unit, component description - GF54.21-P-6040RF

Model 205

Model 253

Shown on model 205.0 with automatic transmission (722/724/725)

Fig 1: Identifying Upper Control Panel Control Unit Components - Shown On Model 205.0

Courtesy of MERCEDES-BENZ USA

Location

The upper control panel control unit is located in the instrument panel in the center above the center console.

Tasks

The upper control panel control unit forwards the signals of the integrated controls and receives the actuation for the integrated display elements. On vehicles with CODE 522 (Audio 20 radio) or CODE 531 (COMAND APS), the upper control panel control unit enables access to the CD or DVD drive on the head unit (A26/17).

The upper control panel control unit receives the following signals:

Actuation of front passenger airbag OFF indicator lamp (N72/1e1) (with CODE U18 (Automatic child seat recognition ACSR [AKSE])) via LCP [UBF] LIN (LIN A3) by the Audio/COMAND control panel (A40/9)
Actuation of front passenger airbag ON indicator lamp (N72/1e2) (with CODE U18 (Automatic child seat recognition ACSR [AKSE])) via LCP [UBF] LIN by the Audio/COMAND control panel
Actuation of ATA [EDW] function indicator (N72/1e3) (with code 551 (Anti-theft alarm system (ATA))) via LCP [UBF] LIN by the Audio/COMAND control panel
Actuation of flashing indicator in hazard warning system button (N72/1s57) via direct line by the front SAM control unit (N10/6)

The upper control panel control unit transmits the following signals:

Actuation of integrated controls via the LCP [UBF] LIN to the Audio/COMAND control panel
Actuation of hazard warning system button via direct line to the front SAM control unit

Shown with manual transmission (716)

Fig 2: Identifying Front Passenger Airbag Indicator Lamp - Shown With Manual Transmission (716)

Courtesy of MERCEDES-BENZ USA

Design

The following controls are located in the upper control panel control unit:

DVD changer load button (with CODE 814) DVD changer))
Single CD/DVD drive button (except code 814 (DVD changer) and except code 520 (Audio 20 USB))
"MEDIA" button (except code 520 (Audio 20 USB))
"NAVI" button (except code 520 (Audio 20 USB))
"RADIO" button (except code 520 (Audio 20 USB))
"TEL" button (except code 520 (Audio 20 USB))
Vehicle button (except code 520 (Audio 20 USB))
Hazard warning system button

The following display elements are located in the upper control panel control unit:

Front passenger airbag OFF indicator lamp (with CODE U18 (Automatic child seat recognition ACSR))
Front passenger airbag ON indicator lamp for automatic child seat recognition (with CODE U18 (Automatic child seat recognition ACSR))
ATA function indicator (with CODE 551 (Anti-theft alarm system (ATA)))

Variants

The number of buttons and display elements in the upper control panel control unit is dependent on the code conditions listed in the "Design" chapter. The location of the buttons in the upper control panel control unit is dependent on the type of transmission (automatic transmission or manual transmission).

Wiring diagram for upper control panel control unit

PE54.21-P-2119-97FBA