Automotive wiring harness is the network main body of automobile circuit, and there is no automobile circuit without wiring harness. Wiring harness refers to the components made of copper stamped contact terminals (connectors) and wires and cables, and then covered with plastic pressed insulators or metal shells, which are tied together by wiring harness to form a connecting circuit. Functionally speaking, there are two kinds of automotive wiring harness: the power line for transmitting power to drive the actuator and the signal line for transmitting input instructions from the sensor. With the continuous improvement of people's requirements for comfort, economy and safety, there are more and more kinds of electronic products in automobiles, and the automotive wiring harness is becoming more and more complicated, and the failure rate of its wiring harness is also increasing accordingly. There are many in automotive wiring harness, and the electric control system is closely related to the wiring harness. Someone once made an image metaphor: if the functions of microcomputer, sensor and actuator are compared to human body, it can be said that microcomputer is equivalent to human brain, sensor is equivalent to sensory organ, and actuator is equivalent to motor tube, then wiring harness is nerves and blood vessels. Automotive wiring harness is the network main body of automobile circuit, which connects the electrical and electronic components of automobile and makes them work. Without wiring harness, there would be no car circuit. At present, whether it is a luxury car or an economical ordinary car, the wiring harness is basically the same, and it is composed of wires, connectors and packaging belts. It is necessary to ensure not only the transmission of electrical signals, but also the reliability of connecting circuits, provide specified current values for electronic and electrical components, prevent electromagnetic interference to surrounding circuits, and eliminate electrical short circuits.