The processing process of the harness is generally: wire opening (wire cutting) → crimping (branch crimping, terminal crimping) → assembly (pre-assembly, winding, marking) → continuity test.

Some problems and solutions in automobile wire harness processing:

1、 Cutting process

Results of poor cutting:

1. Poor stripping size: the next process (crimping) cannot operate normally, and the finished product is unqualified.

2. Poor wire diameter: the wire diameter is too short, resulting in unqualified finished wire.

3. The wire core is damaged and oxidized: poor crimping and false connection.

Defective product handling process: (example of defective product size)

1. Operator: if the size is too short, immediately find out the cause of the nonconformity, communicate with the inspector to solve it, prevent the batch of defective products, and the short size is directly scrapped, and do not mix with the qualified products into the next process; If the size is too long, the inspector will confirm that the wire stripper is used for rework.

2. Inspector: If defective products are found in the spot check, it is required to immediately find out the causes and correct them, and review and deal with the defective products. If there are batches of nonconforming products, they shall be shut down immediately for rectification and reported to the direct leader.

2、 Crimping process

Result of poor crimping:

1. The breaking force is too small: the iron core and the terminal are falsely connected or fall off.

2. Generally, poor crimping will cause a lot of waste, and it is difficult to rework and scrap.

Handling process of defective products: (the breaking force is too small)

1. Operator: If the tension is too small, stop the crimping immediately, contact the technician to adjust the crimping mold and report to the inspector.

2. Inspector: crimping terminals of the same type (qualified in the last inspection until defects are found) are subject to 2% random inspection. If defective products are found, all batches shall be judged as unqualified, terminal marking and isolation shall be carried out, and rework shall be notified.

3、 Assembly process

Result of poor assembly:

1. Terminal withdrawal: If the plug-in terminal is not implemented according to the standard, the terminal withdrawal will be directly sent to the customer without being easily detected. If the terminal is not inserted in place, it will generally cause a virtual connection, resulting in a car burn.

2. Terminal dislocation: ① The wire harness inserted at the wrong terminal hole is cut off on the test bench, which will cause the double rework of the pre-assembly personnel and the tester, and seriously affect the production efficiency. ② If the test area is mixed or missed, the wrong hole position of the terminal will directly cause the short circuit of the vehicle line.

Processing flow of defective products: (wrong hole position of terminal)

1. Operator: ① If the terminal is inserted incorrectly, it should be picked out immediately with a suitable tool and the sheath should be reinserted according to the process standard. Try not to damage components during operation. ② Self-check all sheaths of the same type.

2. Inspector: After self-inspection, the inspector shall check and confirm the sheath type. If the defect is found again, the punishment provisions will be implemented.

4、 Assembly line winding process

Poor pipeline results:

1. The vehicle cannot be loaded due to poor harness size.

2. The branch direction is incorrect - the size is too short when loading.

3. Secondary sub-assembly wiring error - repair or burning.

Defective product handling process: (wrong branch direction)

1. Operator: self-inspection or inspector informs that the branch line direction is wrong, immediately improve it, wrap it according to the correct branch line direction, and uniformly identify, isolate and rework unqualified products.

2. Inspector: If nonconforming products are found in the inspection items, mark and isolate the nonconforming products, and immediately notify the workshop supervisor to explain the cause of defects and assist the workshop in rectification. In case of batch (30) quality problems, the full-time inspector has the right to stop the line for rectification, find out the causes and report to the direct supervisor.

Requirements for conduction test procedure:

1. Identify and isolate the unqualified harness (put it on the repair wire frame according to the model and reason of the unqualified harness);

2. Do not put different types of harnesses on the same wire frame;

3. Do not hang defective products on the wire rack of qualified products;

4. The qualified products shall be packaged within the specified time;

5. Violence is not allowed.