For the outlet position of the moving parts and connectors of the automobile, according to the vibration amplitude of the automobile parts and the maximum movement stroke of the moving parts, there must be enough wire length to avoid the wire harness being subjected to tension or tension. When arranging the wiring harness branches, the selected layout location should be as wide as possible, and the length allowance should be as long as possible. Generally, it should be greater than 25 mm when the wiring harness is slack, so as to prevent the moving parts from causing wear or pulling on the wiring harness during the movement. stress damage.