GF82.85-P-3136CEJ COMAND Controller Unit, Component Description

GF82.85-P-3136CEJ COMAND Controller Unit, Component Description

Component Identification:

Location
The COMAND controller unit is installed into the center console.

Task
The COMAND controller unit fulfills the following tasks:
^ Central operating unit for the entertainment and communication systems integrated into the vehicle
^ Reads in the controls and input signals
^ Evaluation of input factors
^ Activation of output media and system components

Central operating unit for the entertainment and communication systems integrated into the vehicle
The COMAND controller unit provides the user with a structured and uniform interface for the following system components:
- Navigation (map navigation with hard disk as data memory)
- Audio (radio, CD, DVD, Personal Computer Memory Card International Association (PCMCIA) card (MP3 also), MUSIC REGISTER, AUX)
- Telephone (ComTel with phone, address book, email and FM multiplex)
- Video (video DVD and TV operation)
- Voice control system (VCS [SBS]) and text-to-speech

Reads in the controls and input signals
The input factors are read in via the following connections:
^ Direct line
^ Controller Area Network (data bus/CAN bus) (CAN)
^ media-oriented system transport (MOST)

Direct line
The COMAND controller unit has the following direct connections:
- Circuit 30g
- Circuit 31
- AUX input 1 (access in glove compartment)
- FM, AM and CL [ZV] antenna amplifier (A2/18) (model 204.0)
- Rear window antenna amplifier 1 (A2/71) (model 204.2/9)
- Antenna amplifier for rear window FM antenna (A2/19)
- VICS control unit (A2/37)
- Electronic Toll Collection control unit (A50/3)
- Communications control unit (N123/6) (up to 31.5.10)
- Voice control system microphone (B25/7) (2 microphones)
- Backup camera control unit (N66/2)
- Bluetooth antenna (A2/91)
- Multifunction antenna (A28/11)
- TV tuner control unit (N143) (up to 31.5.09)
- Digital TV tuner (A90/3) (as of 1.6.09)

CAN
The COMAND controller unit is an interior CAN (CAN B) subscriber. It communicates with the instrument cluster (A1) and the electronic ignition lock control unit (N73), for example. The COMAND controller unit is a telematics CAN (CAN A) subscriber. It communicates with the Audio/COMAND display (A40/8) and the Audio/COMAND control panel (A40/9), for example.

MOST
The COMAND controller unit is a MOST subscriber and receives control and audio signals from the following control units:
- Digital TV tuner (as of 1.6.09)
- Media interface control unit (N125/1) (with code (518) Media interface)

Evaluation of input factors
The input values are processed in the COMAND controller unit.

Activation of output media and system components
- Audio Out (speaker)
- COMAND fan motor (M4/13) (power supply, speed control and diagnosis)
- Switching voltage for communications control unit (up to 31.5.10)
- Switching voltage for the VICS control unit
- Switching voltage for Electronic Toll Collection (ETC) control unit
- Video out, low voltage differential signal (LVDS) line
The LVDS line transmits picture and video signals from the COMAND controller unit to the Audio/COMAND display via copper lines

Design
The following components are integrated in the COMAND controller unit:
- Control panels for controlling the audio, navigation and telematics functions
- Radio tuner
- Single DVD drive
- Card reader for PCMCIA cards
- Bluetooth receiver for hands-free use of telephone
- Central computer
- Navigation processor
- Hard disk
- Audio amplifier

Function
The buttons on the operating panel of the COMAND controller unit are read in and relayed to the central computer. The signals from the button operations are processed further in the central computer and forwarded via the telematics CAN or 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 respective set audio source is regulated by turning the rotary switch. The function keys switch over to the audio source desired by the user.

These additional functions are also available:

DVD drive
An audio/video CD/DVD can be played using the integrated DVD drive.

Navigation and global positioning system (GPS) control unit
The navigation processor is integrated into the COMAND controller unit and calculates the location of the vehicle using the incoming antenna signals. It also calculates the vehicle's route after the destination has been entered.

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.

Diagnosis
The COMAND controller unit is the diagnosis gateway. The diagnostic communication takes place between the COMAND controller unit and the front SAM control unit with fuse and relay module (N10/1) via the interior CAN. The diagnostic communication between the front SAM control unit with fuse and relay module and the diagnostic connector (X11/4) connected to Star Diagnosis is performed via the diagnostic CAN (CAN D).