About Automotive Wire Harness

Automotive wire harness, also known as low-voltage wires, are different from ordinary household wires. The general household wire is copper single core wire, which has a certain hardness. The car wires are copper flexible wires, some soft wires as thin as hair, several or even dozens of soft copper wires wrapped in plastic insulated pipes (polyvinyl chloride), soft and not easy to break. Because of the particularity of the car industry, the manufacturing process of car wire harness is also more special than other general wire harness.

The system of making car wire harness can be roughly divided into two categories: 

1. Distinguished by European and American countries, including China, Use TS16949 system to control the production process.

2.  Mainly Japan: Such as Toyota and Honda, they have their own systems to control the process. With the addition of car functions and the widespread use of electronic control skills, there will be more and more electrical parts, more and more wires, and the wire harness will become thicker and heavier.

Therefore, the advanced car introduces the CAN bus equipment and chooses the multiplex transmission system. Compared with the traditional wire harness, the multiplex equipment greatly reduces the number of wires and connectors, making wiring easier.

Commonly used.

The common specifications for automotive wire harness are wires with a nominal cross-sectional area of 0.5, 0.75, 1.0, 1.5, 2.0, 2.5, 4.0, 6.0 square millimeters (the nominal cross-sectional areas commonly used in Japanese cars are 0.5, 0.85, 1.25, 2.0, 2.5, 4.0, 6.0, etc.), each of which has allowable load current values. Wires used in electrical equipment of different power. Take the whole vehicle harness as an example, 0.5 specification line is suitable for exterior lights, indicator lights, door lights, top lights, etc.; 0.75 specification line is suitable for license plate lights, front and rear small lights, brake lights, etc.; 1.0 specification line is suitable for turn lights, fog lights, etc.; 1.5 specification lines are suitable for headlights, loudspeakers, etc.; main power lines such as generator pivot line, iron wire and other requirements 2.5 to 4 square mm wire. This only refers to one.

As far as cars are concerned, the key depends on the maximum current value of the load. For example, the iron wire of the storage battery and the positive power cord are used by special car wires alone, and their wire diameters are relatively large, at least more than ten square millimeters. These "giant" wires will not be incorporated into the main wire harness.

Wire Harness Route

Draw the harness diagram beforehand before placing the harness. The harness diagram is different from the circuit schematic diagram. The circuit schematic diagram is a picture that describes the relationship between the various electrical parts. it does not reflect how the electrical components are connected to each other and is not affected by the scale and shape of the various electrical components and the spacing between them. The harness diagram must take into account the size and shape of the electrical components and the spacing between them and reflect how the electrical components are connected to each other.