COMAND controller unit, component description - GF82.85-P-3136CW

MODEL 204.0 with CODE (527) COMAND APS with single DVD drive (with navigation)

MODEL 204.2 with CODE (527) COMAND APS with single DVD drive (with navigation)

Illustrated on model 204.0

Fig 1: Identifying Comand Controller Unit Component - Illustrated On Model 204.0

Courtesy of MERCEDES-BENZ USA

Location

The COMAND controller unit is located in the center console.

Task

The COMAND controller unit is the central operating unit for the entertainment or communication systems integrated into the vehicle. It provides the user with the following system components:

Audio system
Communications System
Navigation system
Voice control system (SBS) and text-to-speech

The COMAND controller unit generates a structured and uniform interface, which is displayed on the Audio/COMAND display (A40/8).

The COMAND controller unit acts as a gateway. It routes the signals from the interior CAN to the telematics CAN and Media Oriented System Transport (MOST) components and forms the communications interface.

In addition to this the COMAND controller unit also supports the following control units:

Sound system amplifier control unit (N40/3) (with code (810) Sound system)
Digital Audio Broadcasting control unit (N87/3) (with code (537) Digital radio)

An external analog audio source can be connected to the COMAND operating, display and controller unit (A40/3) via the AUX jack in the glove box. Data exchange via a discrete line.

Design shown on model 204.0

Fig 2: Identifying Comand Controller Unit - Shown On Model 204.0

Courtesy of MERCEDES-BENZ USA

Design

The COMAND controller unit consists of the following components:

Operating panel for controlling the audio, navigation and telematics functions
DVD drive
Central computer
Navigation processor
Audio amplifier, except code (810) Sound system
Voice control

Function

The panel buttons on the COMAND controller unit are read in and supplied to the central computer. The button operations are processed further in the central computer and forwarded via MOST, the telematics CAN and the interior CAN to the other system components in the form of messages. If the ON button on the COMAND controller unit is pressed, the COMAND controller unit is switched on.

The volume for the set audio source is regulated by turning the ON button. Pressing the function keys enables the user to switch to the desired system components.

DVD drive

The integrated DVD drive can be used to play audio CDs or audio DVDs (including in MP3 format).

Navigation processor and global positioning system (GPS) control unit

The navigation processor is integrated into the COMAND controller unit. As of an active COMAND controller unit, the navigation system compares the GPS data received by the multifunction antenna (A28/11) against the data for the vehicle position and alignment, and against map data. This determines the position of the vehicle. This is then shown on a map on the Audio/COMAND display.

Turn rate sensor

The turn rate sensor determines the direction changes of the vehicle. It is installed into the navigation processor. A calibration is not required.

Voice control system

The VCS is integrated into the COMAND controller unit. The attendant microphone for the voice control system (B25/7) is connected over a discrete line directly to the COMAND controller unit. Pressing on the voice control system button (S111s4) on the multifunction steering wheel (MFL) activates the voice control, and it can be deactivated by pressing the "Back" button and voice control system OFF (S110s4). Once activated, an acoustic signal is sounded. The individual functions of the driver information system are called up and operated via the voice control system (VCS [SBS]).