DTC U1000: Can Comm Circuit: Description
WARNING: This page is about a different car, the 2013 Infiniti M56 and 2013 Infiniti M37. However, it is still accessible from the selected car via links, so may be relevant.
CAN (Controller Area Network) is a serial communication line for real time applications. It is an on-board multiplex communication line with high data communication speed and excellent error detection ability. A modern vehicle is equipped with many ECMs, and each control unit shares information and links with other control units during operation (not independent). --In CAN communication, 2 control units are connected with 2 communication lines (CAN H-line, CAN L-line) allowing a high rate of information transmission with less wiring. Each control unit transmits/receives data but selectively reads required data only.
Refer to "CAN COMMUNICATION SYSTEM: CAN COMMUNICATION SIGNAL CHART " for details of the communication signal.