The traditional point-to-point communication connection method requires a separate loop between each pair of communication nodes. With the increase of electronic control units in the vehicle, the wiring harness of the vehicle is becoming more and more complex, and continuing to use the traditional point-to-point communication method will make the cost and quality of the vehicle higher and higher. In order to solve this problem, in-vehicle network came into being. Among many vehicle-mounted networks, CAN is the most widely used for its unique design, excellent performance and high reliability.
Due to the limited space of the vehicle, the CAN bus is often bundled with other wiring harnesses for wiring. This wiring method makes the CAN bus extremely susceptible to electromagnetic interference. After the CAN bus is subjected to electromagnetic interference, the module will report a code because the signal does not conform to the protocol definition. The main manifestations of the shielding failure of the common CAN bus include signal delay, amplitude change, signal jump, and timing disorder. Signal delay means that the time for the CAN receiver to receive the signal is longer than the time defined by the CAN bus protocol.