CAN Data Link
CAN Data Link
"CAN" is an acronym for Controller Area Network.
The ECM communicates with all data bus capable control modules by a CAN Data Link.
The data bus 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 ECM. Missing information on the data bus is then recognized and stored as a malfunction.
The ECM illuminates the MIL through the CAN data link and tells the MIL to turn on, turn off, or blink.