Controller Area Network (CAN) Data Link
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CAN is an abbreviation for Controller Area Network.
The Engine Control Module (ECM) communicates with all databus capable control modules via a CAN Data Link.
The databus capable control modules (i.e. Engine Coolant temperature Sensor) are connected via two data bus wires which are twisted together (CAN_High and CAN_Low), and exchange information (messages) to the Engine Control Module (ECM). Missing information on the databus is then recognized and stored as a malfunction.
The Engine Control Module (ECM) illuminates the Malfunction Indicator Lamp (MIL) through the CAN data link and tells the Malfunction Indicator Lamp (MIL) to turn on, turn off, or blink.