Touchpad, Component Description - GF54.21-P-4511LF
Model 217, 222
with code 446 (Touchpad only)
Model 217, 222
with code 448 (Touchpad)
Shown with code 446 (Touchpad only)
Shown on model 222.0, as of 01.06.2017 with code 448 (Touchpad)
Shown on model 222.0 as of 01.06.2016 up to 31.05.2017 with code 448 (Touchpad)
Shown on model 222.0, up to 31.05.2016 with code 448 (Touchpad)
Location
The touch pad is located on the center console.
Tasks
The touch pad acts as a central control for the telematics functions. The touch pad can be used to operate the functions shown on the Audio/COMAND display (A40/8). To this end, the touch pad fulfills the following tasks:
- Touch-sensitive registration of control signals
- Receiving signals
- Sending signals
Touch-sensitive registration of control signals
The touchpad enables user input (operation gestures and handwriting recognition) to be detected and the palm rest to be recognized. In addition, the touch pad detects when the following integrated buttons are pressed:
- "Back" button
- Background Audio button (enables operation of the audio source without leaving the current menu)
- Home and Favorites button (enables quick access to the base functions (navigation, radio, media, telephone and Internet, vehicle) and to the functions saved as "favorites")
Receiving signals
The touch pad receives the following signals:
- Circuit 30g (up to model year 2018) or circuit 30t (as from model year 2018) and circuit 31 over a direct line
- CAN messages via telematics CAN (CAN A)
- Operation signals of lower control panel (N72) over the LCP-LIN (LIN A3) (with code 446 (Touchpad only))
Sending signals
The touchpad sends the operation signals as well as operation signals from the lower control panel (with code 446 (Touchpad only)) via the telematics CAN to the COMAND controller unit (A40/3) up to model year 2018, or to the head unit (A26/17) as of model year 2018.
The touchpad sends the following signals:
- Operation signals over the telematics CAN to the COMAND controller unit (up to model year 2018) or to the head unit (as from model year 2018)
- Operation signals of lower control panel (with code 446 (Touchpad only)) over the telematics CAN to the head unit
- Issue of audio signals as operation feedback (with code 446 (Touchpad only)) over the telematics CAN to the head unit, that directly actuates the speaker system on vehicles except code 810 (Sound system), except code 811 (Advanced Sound-System). On vehicles with code 810 (Sound system), the head unit forwards the audio signals over MOST to the sound system amplifier control unit (N40/3), on vehicles with code 811 (Advanced Sound-System) to the Advanced Sound System amplifier control unit (N40/7), which then actuates the speaker system.
Structure
The touch pad features a touch-sensitive operating surface and three integrated buttons.
Variants
The size varies depending on equipment installed. The smaller variant with code 448 (Touchpad) is installed together with the Audio/COMAND control panel (A40/9).
| Wiring diagram for touch pad | A105, model 217, 222 as of model year 2018 with code 448 (Touchpad) or with code 446 (Touchpad only) | PE82.00-P-2061-97SEB | |
| A105, model 217, 222 up to model year 2018 with code 448 (Touchpad) | PE82.00-P-2061-97SEA |