Controller Area Network (Can) Data Link

"CAN" is an abbreviation for Controller Area Network.

The Engine Control Module (ECM) -- communicates with all databus capable control modules by a CAN Data Link.

The databus capable control modules (i.e. Engine Coolant temperature Sensor) are connected by 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.