Automobile wiring harness is the main factor of automobile circuit. Without wiring harness, there is no car circuit. Harness refers to the parts that are made of contact terminals (connectors) and cables stamped with copper materials, and then added with metal material shells or plastic insulation, and then bound by the harness to form a connecting circuit.

Application of automobile wire harness

The harness industry development chain includes cable and wire, connector, processing equipment, harness manufacturing and downstream application industries. The harness has a wide range of uses, and can be used in automobiles, electrical products and various electronic instruments. The body harness connects all the body, and its approximate shape is H type.

Inspection of automobile harness

When leaving the factory, the factory will carry out a series of quality checks and fault tests on each batch of harnesses, and strive to provide customers with perfect harnesses. There may be short circuits, open circuits and poor connections in the harness. Here are some common problems detection methods.

X-ray inspection of harness

The X-ray inspection image of the car harness can clearly show the process defects of the welding points inside the harness, such as solder leakage, tin slag, etc. These defects will directly lead to short circuit of wire harness and cause product quality problems.

Harness tension detection

There is obvious fracture between the transmission line and the transmission line terminal. Open circuit of transmission line is likely to cause failure. It is also possible that the insulation layer of the external cable and the terminal of the transmission line are intact, but the copper core cable in the transmission line and the terminal of the transmission line have been broken. According to the tensile test on the open circuit conductor and transmission line terminal, if the insulation layer of the transmission line and cable gradually thins during the tensile test, it can be determined that the transmission line has been open circuit.

This detection method will damage the appearance of the circuit. If it is an internal open circuit, the image will clearly show the internal status when the X-ray machine is used for inspection.

Harness touch detection

Generally, when the harness is in poor contact, it is likely that there is a problem with the connector. You can touch or drive the relevant connector of the electrical equipment according to the switch power supply of the electrical equipment. After the connector is connected, the electrical equipment suddenly works normally or abnormally, indicating that the connector is faulty and needs to be tested.

Harness test lamp detection

In some harnesses, the external cable insulation layer of the transmission line and the connection terminal of the transmission line are intact, but the copper-core cable in the transmission line and the connection terminal of the transmission line have been disconnected, which will also lead to the disconnection of the transmission line. The harness connectors at both ends can be detected through the watt-hour meter or test lamp to detect the short circuit fault of the circuit.

The importance of X-ray nondestructive testing lies in the quality and process inspection, while the circuit inspection is the performance inspection of the harness. Both are essential. Only by ensuring quality and performance can the harness be handed over to the customer in good condition.