2009 BMW 528xi AutomaticFACTORY OEM SERVICE PROCEDURE

Multi-audio system controller

  • System master

    The system master connects the individual control units in the M-ASK.

  • Power master

    The power master initializes the network and switches the MOST bus on and off (wake-up, sleep mode).

  • Network master

    The network master controls and monitors the MOST bus. Each time the network is started, the exact system configuration is recorded and compared with a stored target configuration.

    If systems do not work correctly, these are reset and separated from the MOST bus. Any operating fault of the network or any deviation from the target configuration is stored in a fault memory for the MOST bus.

  • Audio master

    The Audio master collects all the audio signals in the vehicle, processes the audio signals and outputs them over the loudspeakers. The audio master also produces additional audible signals for warnings and for Park Distance Control (PDC). By mixing or fading in and out, a "softer" audible change is obtained between the signal sources.

  • Connection master

    The connection master distributes the signals of the audio sources and the audible signals to the loudspeakers. The signals are transmitted to the loudspeakers in the following way:

    • Front left and right (acoustic signals, telephone, messages from the navigation system, traffic information announcements)
    • Front left and right, rear left and right (signals for PDC)
    • All loudspeakers (all sources in the "Entertainment" menu)
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  • β€’ You smell fuel, burning insulation, or see smoke.
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  • β€’ You are missing required tools, torque specs, or safe lifting equipment.
  • β€’ You are not confident in the next step or safety outcome.

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