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Controller Area Network Data Link






Controller Area Network Data Link

The engine control module (ECM) communicates with data bus capable control modules via a CAN Data Link.

The data bus capable control modules are connected via data bus wires, which are twisted together (CAN high and CAN low), and exchange information with the ECM. Missing or implausible information on the data bus is recognized and stored as a malfunction based on specific DTC criteria.

The malfunction indicator lamp (MIL) is illuminated as a result of a CAN message sent by the ECM. The MIL can be turned on, turned off, or blink, depending on the message received.