In modern cars, there are especially many automotive wiring harnesses, and the electronic control system is closely related to the wiring harness. Someone once made an image analogy: if the function of microcomputer, sensor and executive element is compared to the human body, it can be said that the microcomputer is equivalent to the human brain, the sensor is equivalent to the sensory organ, and the executive element is equivalent to the motor organ, then the wiring harness is a nerve and blood vessel. Automotive wiring harness is the main body of the network of automobile circuits, connecting the electrical and electronic components of the car and making them functional, without wiring harnesses, there is no automotive circuit.

At present, whether it is a high-end luxury car or an economical ordinary car, the form of wiring harness is basically the same, which is composed of wires, plug-ins and wrapping tape, which not only ensures the transmission of electrical signals, but also ensures the reliability of the connecting circuit, supplies the specified current value to the electronic and electrical components, prevents electromagnetic interference to the surrounding circuits, and eliminates electrical short circuits. Automotive wiring harnesses are divided into two types: power lines that carry power to drive actuators (actuators) and signal lines that transmit sensor input commands. Power lines are thick wires that carry large currents, while signal lines are thin wires that do not carry electricity (optical fiber communication); For example, the cross-sectional area of the conductor used in the signal circuit is 0.3 and 0.5mm2. The cross-sectional area of the wire used in the motor and the actuator is 0.85, 1.25mm2, while the cross-sectional area of the wire used in the power circuit is 2, 3, 5mm2; Special circuits (starter, alternator, engine grounding wire, etc.) are available in 8, 10, 15, 20mm2 specifications.

The larger the wire cross-sectional area, the greater the current capacity. The choice of wire, in addition to considering electrical performance, is also subject to the physical performance of the vehicle, so its choice is wide. For example, the wires between the frequently opened/closed doors on a taxi car and the straddling body should consist of wires with good flex properties. Conductors used in parts with high temperatures generally use vinyl chloride and polyethylene-coated wires with good insulation and heat resistance. In recent years, the use of electromagnetic shielded wires in weak signal circuits has also increased. With the increase of automobile functions, the widespread application of electronic control technology, more and more electrical parts, more and more wires, the number of circuits and power consumption on the car has increased significantly, and the wiring harness has become thicker and heavier. This is a big problem that needs to be solved, how to make a large number of wiring harnesses in a limited automotive space how to arrange more effectively and reasonably, so that automotive wiring harnesses play a larger function, has become a problem faced by the automobile manufacturing industry.