CD player with changer, function - GF82.64-P-3113-02RB

CD player control 

The CD player with changer (A2/6) is actuated via the Digital Data Bus (D2B) and an electrical wake-up line by the radio (A2) or the COMAND operating, display and control module (A40/3) depending on the vehicle equipment.

The CD player with changer (A2/6) generates messages for the following operating states:

• No magazine in CD changer
• Magazine occupation (music CDs only)
• Number of current CD
• Number of current title
• List of occupied slots (CDs)
• Number of titles per disc
• Current operating state (acoustic reproduction of radio signals, pause, etc.)

The messages are transmitted via the digital data bus (D2B), and displayed by the radio (A2) or by the COMAND operating, display and control module (A40/3).

CD playback 

The audio data is stored on the CD-ROM. The audio CD is driven by a motor in the CD player. The laser-optical device scans the side of the rotating CD with no label without touching and converts the digital optical signals into electric signals. Small missing areas resulting from scratches or contamination on the audio CD are later interpolated by a DA converter and thereby compensated.

The electric signals are then decoded in the CD changer and transmitted via the digital data bus (D2B), to the COMAND operating, display and control module (A40/3) or to the radio (A2).

The decoded signals are relayed by the COMAND operating, display and control module (A40/3) or by the radio (A2) through the audio signal processing and sound amplifier (A2/13) to the loudspeakers.

Jumps and interruptions during playback 

When driving on poor roads and during strong vibrations it may be that jumps and interruptions occur during playback. In such cases CD playback should be put on hold until the condition of the road improves.

Moisture can collect in the CD player housing during wet weather or when the ambient temperature varies highly (condensation). This may also lead to faults occurring during playback. In such cases, the CD player should be sufficiently ventilated.