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Controller Area Network Data Link






Controller Area Network Data Link

The Engine Control Module (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 which exchange information to the ECM. Missing information on the data bus is then recognized and stored as a malfunction.

The ECM illuminates the malfunction indicator lamp (MIL) through the CAN data link and tells the MIL to turn on, turn off, or flash.