Electrical and assembly
Cable and wire harness manufacturing: what goes wrong and where to inspect
Wire harnesses connect everything in vehicles, machines and appliances. Crimp quality and correct routing are the difference between a reliable machine and intermittent faults.
01How the process works
Wires are cut, stripped and crimped to terminals by automatic machines, then assembled into connectors on harness boards, taped or sleeved, and electrically tested on test tables.
Crimp height, pull force and cross section analysis prove crimp quality; electrical testing proves continuity and correct pinning. Workmanship follows IPC/WHMA-A-620.
- Cut and strip. Wires cut to length and stripped.
- Crimping. Terminals crimped with monitored presses.
- Assembly. Pinning into connectors on harness boards.
- Taping and sleeving. Bundles formed.
- Electrical test. Continuity, shorts, pinning.
02What typically goes wrong
| Defect | Typical cause | How it is found |
|---|---|---|
| Incorrect crimp height | Applicator wear, set-up | Crimp height micrometer |
| Low pull force | Wrong terminal, strip length | Pull test |
| Strands cut or outside crimp | Stripping | Visual, cross section |
| Wrong pinning | Assembly error | Electrical test |
| Terminal not locked | Insertion | Push back test |
| Damaged insulation | Handling | Visual, hipot |
03Where an inspector should look
Before production
- Drawing and wire list
- Applicator qualification
- Test program
During production
- Crimp height and pull at set-up
- Crimp force monitoring
After production
- 100% electrical test
- Visual to IPC/WHMA-A-620
- Labels and packing
04Standards and references
IPC/WHMA-A-620 (cable and harness assemblies), USCAR-21 (crimp performance), IEC 60352-2.
Standards are named for orientation. The applicable edition and acceptance criteria are those in your contract and specification.