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Most Network

Fig 1: Identifying MOST Network Control Modules (Up To Eight)
GLL102072Courtesy of VOLVO CARS CORPORATION

The MOST network can consist of up to eight control modules.

The infotainment control module (ICM) monitors the MOST network and manages communication. The infotainment control module (ICM) is monitored by the central electronic module (CEM) on the controller area network (CAN). In addition to the infotainment control module (ICM), there are two control modules which are standard on the MOST network. These are:

The table below lists all the control modules which may be included in the MOST network.

Explanation 

CAN  = Controller Area Network, electrical network for communication

LS CAN  = low speed side of the CAN

MOST  = Media Oriented Systems Transport, fiber optic network for communication

Master control module  = Control module which monitors the MOST network

Slave control module  = Control module which supplies the MOST network functions

Option  = accessory installed at the factory during the purchase of a new car

Accessory  = after market installation

(x)  = position number in the illustration

Control module Function Communication Other
Infotainment Control Module (ICM) (1) Monitors the MOST network. The master control module is connected to both the LS CAN and the MOST network. Included in the standard set-up of the MOST network. Must be connected to the MOST network to function.
Multimedia Module (MMM) (2) Displays traffic information on the directly connected display screen. Slave module on the MOST network. Option, accessory
Phone module (PHM) (4) Controls carphone functions. Connected to the LS CAN and is a slave module on the MOST network. Option, accessory
MD module (MP1) (3) Plays minidisks. Slave module on the MOST network. Option, accessory
CD module (MP2) (5) Plays CDs. Can consist of a CD player or CD changer Slave module on the MOST network. Option, accessory
Antenna module (ATM) (8) Consists of an AM/FM antenna. May also have a GPS unit and TMC unit as an option. Slave module on the MOST network. Included in the standard set-up of the MOST network.
Audio module (AUD) (6) Amplifier connected to all loudspeakers except the subwoofer module (SUB). The microphone and headset panel are also directly connected to this control module. Slave module on the MOST network. Included in the standard set-up of the MOST network.
Subwoofer module (SUB) (7) Amplifier and bass speakers integrated in the same unit. Slave module on the MOST network Option, accessory.
The audio module (AUD) must be connected to the MOST network for the subwoofer module (SUB) to function.