XC90 FWD L6-3.2L VIN 98 B6324S (2007)
A MOST network with all control modules.
An open circuit occurs on the cable between the Audio module (AUD) and the Accessory USB unit (AUU), see figure.
The infotainment control module (ICM) receives responses up to and including the Accessory USB unit (AUU) and presents the value 4.
If there was no open-circuit, the infotainment control module (ICM) would have responded "OK.
Network Design
Network design
General
The MOST network is an optical network in which all control modules included are connected in a ring. All messages in the MOST network travel in
one and the same direction from the infotainment control module (ICM) to the Subwoofer module (SUB).
In a fiber optic network, light pulses are transmitted instead of electrical signals. The light pulses are interpreted in the same way as the electrical signals
on the CAN network.
The MOST network uses the master-slave concept. This means that a master control module, infotainment control module (ICM) has overall control of
communication on the MOST network.
The fiber optic cable is made of plastic. Communication is using red light on a wavelength of 650 nm.
The optical connector
