What Is CAN Bus?

Controller Area Network — a robust vehicle bus standard that allows microcontrollers and electronic control units to communicate without a host computer.

The CAN bus is the backbone of modern vehicle communication, connecting the ECM, TCM, ABS module, airbag module, body control module, and many other electronic control units. It uses a twisted pair of wires (CAN High and CAN Low) and operates at speeds up to 1 Mbps. CAN bus failures trigger U-codes (network communication codes) and can affect multiple vehicle systems simultaneously.