M-ASK / CCC And CID

For the instrument cluster, the M-ASK and CCC serve as an interface to the Central Information Display (CID). The CID displays detailed texts concerning Check-Control messages and information about CBS and other on-board computer functions. The CID also enables the driver to change the units of measurement (e.g. Celsius to Fahrenheit, and vice versa) for the instrument cluster.

Moreover, the M-ASK and CCC establish a telephone connection when a CBS serve operation is due (= TeleService). This is achieved by sending a message to the telephone control unit via the MOST.

Other control units communicate via the bus to send messages (Check-Control messages) to the instrument cluster. The instrument cluster emits these Check-Control messages via symbols in the LCD display.