Automotive wiring harness is the network subject of automobile circuit, and there is no automobile circuit without wiring harness. The wiring harness refers to the assembly which is made of copper material, after the contact terminal is pressed with the wire and cable, the insulator or metal shell is pressed on the outside, and the wiring harness is bundled to form the connecting circuit. The wiring harness industry chain includes wires and cables, connectors, processing equipment, wiring harness manufacturing and downstream application industries. The wiring harness is widely used in automobiles, household appliances, computers and communication equipment, various electronic instruments and meters, etc. The wiring harness of the car body connects the whole car body and is generally H-shaped. The common specifications of wires in automotive wiring harness have nominal cross-sectional area, and each has allowable load current value, which is suitable for wires of different power consumption equipment.