GF82.85-P-2030CEJ Audio mode, function
GF82.85-P-2030CEJ Audio Mode, Function
- with CODE (527) COMAND APS with single DVD drive (with navigation)
- with CODE (498) Japan version
Function requirements, general
^ Circuit 30g On or Circuit 15R On
^ Cockpit Management and Data System (COMAND) authorized and working correctly
^ No fault in antenna system (radio function)
^ Data DVD/CD inserted
The circuit 15 status is sent by the electronic ignition lock control unit (N73) to the interior CAN (CAN B).
Audio mode, general
Following audio functions can be selected using the RADIO menu or the DISK menu
^ Radio mode function sequence (AM/FM)
^ Function sequence for audio DVD/CD and MP3
^ Music Register function sequence
The following components are available for control of the audio system:
- Control buttons on the COMAND control unit (A40/3)
- Audio/COMAND control panel (A40/9)
- Left multifunction steering wheel button group (S110) and right multifunction steering wheel button group (S111)
- Voice control system microphone (B25/7)
The audio output takes place via the COMAND control unit on the following speakers:
- Left front door speaker (H4/1)
- Right front door speaker (H4/2)
- Left rear door speaker (H4/3)
- Right rear door speaker (H4/4)
If Circuit 15R Off, the COMAND control unit activates the Media Oriented System Transport (MOST) users when it is switched on.
Information on the currently set stations or played title is indicated in the instrument cluster (A1) and Audio/COMAND display (A40/8).
Radio mode function sequence (AM/FM)
The antennas in the rear window receive the signals for the FM and AM (MW, LW, SW) radio frequency bands.
The following signals relevant for the radio reception are modulated onto these signals:
- Music signals
- Speech signals
- Data signals (e.g. traffic information)
The signals are sent via direct lines to the rear window FM antenna amplifier (A2/19) (model 204.0/2), to the TV 1 and DAB Band III antenna amplifier (A94/1) (model 204.9), to the FM, AM and CL antenna amplifier (A2/18) (model 204.0) and to the rear window antenna amplifier 1 (A2/71) (model 204.2/9).
The antenna amplifiers filter the frequencies of the radio frequency bands out of the received signals and amplify them. The amplified signals are then sent via the coaxial lines to the tuners integrated into the COMAND control unit where they are demodulated and output on the speaker system.
The radio mode function comprises the following subfunctions:
^ AM reception function (MW, LW, SW)
^ FM reception function (FM)
AM reception function (MW, LW, SW)
For the MW, LW and SW radio frequency bands, the useful signals are broadcast using amplitude modulation.
These signals are demodulated by the AM tuner integrated into the COMAND control unit. In other words, it also separates the useful signals (audible frequencies) from the carrier signal (inaudible).
The COMAND control unit also enables an additional automatic reception-specific changeover between the antenna amplifiers.
FM reception function (FM)
In the FM radio frequency band, the useful signals are broadcast using frequency modulation. These signals are demodulated by the FM tuner integrated into the COMAND control unit. In other words, it also separates the useful signals (audible frequencies) from the carrier signal (inaudible). The COMAND control unit also enables an additional reception-specific changeover between the two antenna amplifiers.
Function sequence for audio DVD/CD and MP3
A single-slot DVD drive is integrated into the COMAND control unit. The audio DVD/CD function can be used to play audio DVDs or audio CDs (including MP3 format). User guidance for controlling DVD/CD functionality and displaying supplemental information is carried out via the audio/COMAND display (A40/8). Data exchange is accomplished between the COMAND control unit and Audio/ COMAND display via the telematics CAN (CAN A) for control of the DVD/CD functions (e.g. title selection). The signals for displaying the menu and additional information (e.g. titles) are transferred over a Low Voltage Differential Signal (LVDS) line.
Music Register function sequence
On the integrated hard drive in the COMAND control unit, files (in the MP3 format) can be stored from a CD/DVD of a Personal Computer Memory Card International Association (PCMCIA) and then called up as required.
