Take the cabin grounding point of a certain model as an example. The grounding point includes both series grounding and parallel grounding: headlights, fog lights, daytime running lights, headlight height adjusters, and front horns are all low-power electrical appliances, and electronic fans It belongs to high-power electrical appliances, and they belong to the type that can share the ground; the grounding loop of the electronic fan adopts a parallel grounding method to prevent other electrical appliances from connecting to the grounding trunk and reduce interference to other electrical appliances; treble and bass electric horns are grounded, The left front fog lamp and the daytime running lamp are grounded. The grounding voltage and current of these two branches are not much different, and they can be grounded in series to control the cost of wires.