High Speed Controller Area Network (CAN)
The high speed CAN is based on SAE J2284, ISO-11898, and is a serial communication language protocol used to transfer messages (signals) between electronic control modules or nodes. Two or more signals can be sent over one CAN circuit allowing 2 or more electronic modules or nodes to communicate with each other. This communication, or multiplexing, network operates at 500k/sec (kilobytes per second) and allows the electronic modules to share their information messages.
Included in these messages is diagnostic data sent over the CAN+ and CAN- lines to the DLC. The PCM connection to the DLC is typically done with a 2-wire, twisted pair cable used for network interconnection. The diagnostic data such as self-test or PIDs can be accessed with a scan tool. Information on scan tool equipment is described in the DIAGNOSTIC METHODS article, Diagnostic Methods.