mercedes can bus
W211 and later: Communication Networks
The W211 E-class and following models (W164, W169, ...) uses many control modules that share information, control consumers and self diagnostics. There are 3 vehicle communication networks and 1 dedicated diagnostic network:
- CAN B - Interior databus (sometimes called body CAN)
- CAN C - Engine databus (sometimes called chassis CAN)
- MOST - Digital fiber optic databus (replaces D2B)
- CAN D - Diagnostic databus
Central Gateway Module - CGW
- CGW is the primary gateway between CAN C and CAN B
- Version coding known from EIS (N73) is now contained in CGW (N93)
- CGW contains FSS plus maintenance programs, no longer in ICM
- CGW module replacement: CGW module attempts to adapt to vehicle control modules. System diagnosis knowledge base updated by flashing.
- Incorporates system diagnosis functions. CGW replaces system diagnosis module known from (R230) It monitors, evaluates and performs logic assessments of CAN B related components (later production CAN C will be included)
MOST is fiber optics manufactured with greater durability than D2B, Communication standard created by DCAG, Becker, and other corporations.
The MOST acronym is derived from it’s definition as a “Media Oriented System Transport”. The configuration of the system is a combination of ring and star topology similar to D2B.