First, the electrical layout engineer shall provide the functions of the electrical system, electrical load and related special requirements. The state of electrical parts, installation position, wiring harness and electrical parts butt joint form.

2. According to the electrical functions and requirements provided by the electrical layout engineer, the electrical schematic diagram and circuit diagram of the vehicle can be drawn.

Third, according to the electrical principle circle to each electrical subsystem and loop energy distribution, including the power supply tie wire, and the distribution of the junction point.

Four, according to the distribution of electrical parts of each subsystem, determine the wiring form of wiring harness, the electrical parts connected by each harness and the direction of the car; Determine the outer protection form of wire harness and the protection through hole; Determine the fuse or circuit breaker according to the electrical load; Determine the wire diameter according to the amount of fuse or circuit breaker; According to the function of electrical parts, according to the relevant standards to determine the wire color; Determine the type of terminal and sheath on the wire harness according to the connector of the appliance itself.

Draw two - dimensional wiring harness diagram and three - dimensional wiring harness layout diagram.

Six, according to the approved three-dimensional wiring harness layout diagram, check the two-dimensional wiring harness diagram, two-dimensional wiring harness diagram accurate can be issued, after approval, can be according to the wiring harness diagram trial-production, production.

Description of the above 6 processes is too general, the specific process of automotive wiring harness design, will encounter a lot of such and such problems, need wiring harness designer calm and calm analysis, to ensure the rationality and reliability of wiring harness design, ensure the smooth circuit design of the vehicle.