That is to say, the high-voltage wiring harness of electric passenger vehicles is arranged outside the vehicle, so it is necessary to carry out mechanical protection and dust-proof and waterproof design for the high-voltage wiring harness of electric passenger vehicles. In order to improve the mechanical protection and dustproof and waterproof performance of the high-voltage wiring harness, protective measures such as sealing rings are used between the plugged connectors and the position where the connectors are connected to the cables to prevent the entry of water vapor and dust, so as to ensure the sealing environment of the connectors and avoid Risk of short circuits between contacts, as well as safety issues such as preventing the entry of moisture and avoiding sparks. For the high-voltage wiring harness arranged in the engine compartment and the chassis, special attention should be paid to the protection method of the wiring harness. The high-voltage wiring harness arranged in the chassis part should fully consider the vehicle wading, scraping the chassis, etc., when arranging and designing the high-voltage wiring harness, fully consider the factors such as waterproof, anti-sand splashing, anti-scratch and other factors, and can use plastic wire grooves, metal elbows Designed to protect high voltage wiring harnesses. The wire trough considers the assemblability, and the guide groove of the sub-slot cover fastens the high-voltage wire harness and fixes it on the bottom plate of the vehicle. The metal bending process is complicated and easy to install. At present, most high-voltage wiring harnesses use coatings to protect the high-voltage wiring harnesses. The functions of the coatings are mainly anti-wear, noise reduction, radiant heat insulation, and beautiful appearance. Generally, orange high-temperature flame-retardant bellows or orange high-temperature flame-retardant bellows are used. Cloth sleeves are fully covered.