GF82.85-P-2030GQ Audio Mode, Function
GF82.85-P-2030GQ Audio Mode, Function
- with CODE (525) MB Audio 50 APS radio
Function requirements, general
^ Status circuit 30 On
^ The Auto pilot system (APS) is operating properly
^ No fault in antenna system (radio function)
^ Medium for playback is available and free of error (DVD/CD mode or AUX function)
General information on the audio mode
The following audio functions can be selected using the "Audio" menu item
^ Function sequence for radio mode (FM/MW/LW/SW)
^ Function sequence for DVD drive (single slot)
^ AUX function sequence (without code (518) Media interface)
Further partial functions are described in separate documents:
^ Digital audio broadcasting (DAB), function (with code (537) Digital radio)
^ Media interface function (with code (518) Media Interface)
Operating instructions
Audio functions are operated using the following components:
- Left multifunction steering wheel button group (S110)
- Right multifunction steering wheel button group (S111)
- Control panels on the radio and navigation unit (A2/56)
With circuit 15R Off, the Media Oriented System Transport MOST) subscribers are activated when the radio and navigation unit is switched on.
Function sequence for radio mode (FM/MW/LW/SW)
The rear window antennas or the FM/AM/RRCL [FZV] antenna (A2/93a1) in the roof antenna module (A2/93) receive high frequency (HF) signals for the FM and AM (MW, LW, SW) radio frequency bands. The following useful signals relevant for the radio reception are found on these HF signals:
- Music signals
- Speech signals
- Data signals (e.g. Traffic Message Channel (TMC) messages (traffic information))
The HF signals from the rear window antennas are forwarded via direct lines to the FM rear window antenna amplifier (A2/19) and from there to the roof antenna module. These two amplifiers filter the frequencies of the radio frequency bands out of the received HF signals and amplify them. The amplified signals are then sent from the roof antenna module via coaxial lines (FM, AM) to the tuner integrated into the radio and navigation unit, demodulated and then undergo final amplification.
The demodulated audio signals on vehicles with code (810) Sound system are routed by the radio and navigation unit via MOST to the amplifier for sound system (N40/3) where they then undergo final amplification. The audio is then output by the following speakers via direct lines:
- Left rear door speaker (H4/3)
- Right rear door speaker (H4/4)
- Speaker Left front door (H4/5)
- Right front door speaker (H4/6)
- Center cockpit speaker (centerfill) (H4/27)
- Left front door tweeter (H4/33)
- Right front door tweeter (H4/34)
- Left rear door tweeter (H4/35)
- Right rear door tweeter (H4/36)
- Left rear surround speaker (H4/54)
- Right rear surround speaker (H4/57)
The audio signal for the subwoofer (H4/29) travels from the radio and navigation unit to the amplifier for the sound system via MOST and from there, via direct lines to the subwoofer amplifier (N40/9) and then to the subwoofer speaker.
In vehicles without code (810) Sound system, the audio signals are finally amplified in the radio and navigation unit and then output via direct lines over the following speakers:
- Left rear door speaker
- Right rear door speaker
- Left front door speaker
- Right front door speaker
- Left front door tweeter
- Right front door tweeter
- Left rear door tweeter
- Right rear door tweeter
The Radio mode function sequence also includes the following subfunction sequences:
^ Function sequence for AM tuner (MW, LW, SW)
^ Function sequence for FM twin tuner with phase diversity (FM/TMC)
^ Radio Data System (RDS) function sequence
Function sequence for AM tuner (MW, LW, SW)
For the MW, LW and SW radio frequency bands, the useful signals are broadcast using amplitude modulation (AM). These signals are demodulated by the AM tuner integrated into the radio and navigation unit. In other words, it separates the useful signals (audible frequencies) from the carrier signal (inaudible).
Function sequence for FM twin tuner with phase diversity (FM/TMC)
For the FM radio frequency band, the useful signals are broadcast using frequency modulation (FM). These signals are demodulated by the FM twin tuner integrated into the radio and navigation unit.
In other words, it also separates the useful signals (audible frequencies) from the carrier signal (inaudible). The radio and navigation unit also enables an additional reception-specific changeover between the two antenna amplifiers.
RDS function requirements
^ An RDS station is tuned in.
^ The "RDS" function is activated
Function sequence for RDS
Digital, inaudible information such as station names, type of program (PTY) (e.g. pop, culture) that is broadcast by RDS stations is evaluated by the radio and navigation unit and shown on the display.
Function sequence for DVD drive (single slot)
A DVD drive is integrated into the radio and navigation unit. This enables audio CDs and MP3 DVDs to be played.
User guidance for controlling DVD/CD functionality and displaying supplemental information takes place in the radio and navigation unit display. In vehicles with code (810) Sound system, the data exchange between the radio and navigation unit and the sound system amplifier takes place via the MOST. The audio output takes place over the following speakers:
- Left rear door speaker
- Right rear door speaker
- Left front door speaker
- Right front door speaker
- Center cockpit speaker (centerfill)
- Left front door tweeter
- Right front door tweeter
- Left rear door tweeter
- Right rear door tweeter
- Left rear surround speaker
- Right rear surround speaker
The audio signal for the subwoofer speaker travels via MOST from the radio and navigation unit to the sound system amplifier and from there, via the subwoofer amplifier along direct lines to the subwoofer speaker.
In vehicles without code (810) Sound system, the audio signals are finally amplified in the radio and navigation unit and then output via direct lines over the following speakers:
- Left rear door speaker
- Right rear door speaker
- Left front door speaker
- Right front door speaker
- Left front door tweeter
- Right front door tweeter
- Left rear door tweeter
- Right rear door tweeter
The DVD/CD menu and the Track menu, which are stored on the inserted DVD/CD, are shown on the display of the radio and navigation unit. For this reason, the function scope and menu display are dependent on each respective medium.
AUX function sequence (with code (518) Media interface)
If an external device (e.g. MP3 player) is connected via the AUX jack and the "AUX" menu item is called up, the corresponding base screen then appears on the display of the radio and navigation unit.
The following functions are shown in the display:
- Title name
- Elapsed title time
- Album name, if present
- Playback lists
- Playback options
In vehicles with code (810) Sound system, the data exchange between the radio and navigation unit and the sound system amplifier takes place via the MOST. The audio output takes place over the following speakers:
- Left rear door speaker
- Right rear door speaker
- Left front door speaker
- Right front door speaker
- Center cockpit speaker (centerfill)
- Left front door tweeter
- Right front door tweeter
- Left rear door tweeter
- Right rear door tweeter
- Left rear surround speaker
- Right rear surround speaker
The audio signal for the subwoofer speaker travels via MOST from the radio and navigation unit to the sound system amplifier and from there, via the subwoofer amplifier along direct lines to the subwoofer speaker.
In vehicles without code (810) Sound system, the audio signals are finally amplified in the radio and navigation unit and then output via direct lines over the following speakers:
- Left rear door speaker
- Right rear door speaker
- Left front door speaker
- Right front door speaker
- Left front door tweeter
- Right front door tweeter
- Left rear door tweeter
- Right rear door tweeter
