CAN-bus, checking (from MY 2000): Function

The Engine Control Module (ECM) communicates with all control modules capable of data bus via CAN data bus.

The control modules capable of data bus are connected together via two data bus wires twisted together (CAN high and CAN low) and exchange information (messages). Missing information on the data-bus is recognized as a malfunction by the Engine Control Module (ECM) as well as by other CAN -bus control modules.