With code (527) COMAND APS with Single DVD disk drive (with navigation) Except code (498) Japanese version - GF82.85-P-2030RCD

MODEL 171 with CODE (527) COMAND APS with single DVD drive (with navigation) except CODE (498) Japan version 

MODEL 171 as of model year 09/YoM 08 model refinement package 

Function requirements  Status "Circuit 30 ON"; Cockpit Management and Data System (COMAND) operating properly; No fault in antenna system (radio function); The medium to be played is available and correct.

General  The Audio mode consists of the following function sequences which can be activated with the menu item Audio: Function sequence for radio mode (FM/MW/LW/SW); Player function sequence; General Music Register.

A further subfunction is described in a separate document:  Digital Audio Broadcasting (DAB) function, with code (537) Digital radio and with code (833) Great Britain version

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 of the COMAND operating, display and controller unit (A40/3); Voice control system.

Function sequence for radio mode (FM/MW/LW/SW) The rod antenna (A28) receives high frequency (HF) signals for the radio frequency bands FM and AM (MW, LW, SW). The following useful signals relevant for the radio reception are modulated onto these HF signals:  Music signals - Speech signals - Data signals (e.g. Traffic Message Channel (TMC) messages (traffic information))

The HF signals are routed to the left antenna amplifier module (A2/64) via direct lines. The left antenna amplifier module filters the radio frequency band frequencies from the HF signals received, and amplifies these. The amplified signals are then sent over coaxial lines (FM, AM) to the tuner integrated into the COMAND operating, display and controller unit where they are demodulated.

The demodulated audio signals in vehicles with code (810) Sound system are routed from the COMAND operating, display and controller unit via the Media Oriented System Transport (MOST) to the sound system amplifier (N40/3) where they undergo final amplification. The audio is then output by the following speakers via direct lines:  Left door speaker group (H4/1) - Right door speaker group (H4/2) - Left rear speaker (H4/7) - Right rear speaker (H4/8) - Center cockpit speaker (centerfill) (H4/27) - Left door tweeter (H4/33) - Right door tweeter (H4/34) - Left rear surround speaker (H4/54) - Right rear surround speaker (H4/57)

For vehicles except code (810) Sound system, the audio signals undergo final amplification by the COMAND operating, display and controller unit and then sent to the following speakers via direct lines:  Left door speaker group - Right door speaker group - Left rear speaker - Right rear speaker - Center cockpit speaker (centerfill) - Left door tweeter - Right 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 SW, MW and LW radio frequency bands, the useful signals are broadcast using amplitude modulation (AM). The AM tuner integrated into the COMAND operating, display and controller unit demodulates these signals. 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)  It separates the useful signals (audible frequencies) from the carrier signal (inaudible). The COMAND operating, display and controller unit also performs changeovers depending on the reception quality.

RDS function requirements  An RDS station is tuned in. The "RDS" function is activated

Function sequence for RDS  Apart from the normal radio program, many radio stations (FM) transmit additional digital information such as station names, program type (PTY) (e.g. pop, culture, etc.) and traffic program identification. This information is evaluated by the COMAND operating, display and controller unit and appears on the display of the COMAND operating, display and controller unit: