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Harnesses and Cable Assemblies Troubleshooting Guide


Cable assemblies and harnesses are two products with different purposes. It is sometimes possible to confuse the two terms.

Harness consists of multiple wires and a thermoplastic or thermoset outer sheath that, due to the nature of the outer sheath, cannot be used in a wide range of applications in harsh and demanding environments.

Cable assemblies, on the other hand, also consist of multiple wires and an outer sheath, but the sheath of a cable assembly is made of a heavy-duty material that can withstand environmental stresses. Explore the manufacturing and differences between cable assemblies and harness assemblies.

Cable assemblies and harnesses can also face some failures

Common problems with cable assemblies

  • Not choosing the correct cable. The performance of the selected cable assembly is different for different applications. Improperly selected performance that is not durable enough or does not hold up well may lead to product strikes
  • Improper installation. Incorrect soldering work and tooling setup can also affect its performance.
  • Improper testing.

Common problems with wire harness assemblies

  • Improper layout
  • Wire preparation
  • Improper labeling
  • Defects related to soldering
  • Missing components
  • Improper wire tying

Intermittent Errors in Cable Assemblies and Harnesses

Common intermittent errors in cable assemblies and harnesses include open circuits, short circuits, and miswiring.

Possible causes for the above are

  • Improper setup
  • Improper pin contact
  • Worn or dirty contacts
  • Weak contacts

Despite taking a number of steps to avoid errors in cable assemblies and harnesses, errors can still occur. At this point, it is important to thoroughly test the cable assemblies and harnesses. Some common test methods are

Mechanical Performance Testing

Some of the mechanical properties items to be tested include

  • Elongation
  • Tensile strength
  • Flexibility
  • Impact resistance

Environmental test

This test is mainly to confirm whether it can withstand environmental conditions

  • Temperature
  • Humidity
  • Vibration
  • Dust, etc.

Electrical test

It mainly involves the following

  • Open wire
  • Improper wiring
  • Risk of short circuit

Visual testing

Ensuring all components are in good condition

  • Wire and cable condition
  • Correctness of connectors
  • Labeling correctness

Signal integrity testing

Evaluate the signals that can be carried by cable assemblies and harnesses, and also check for crosstalk and signal error issues.

To summarize

Proper use of troubleshooting mechanisms and appropriate testing methods ensure that you do not encounter performance problems with cable assemblies and harnesses.

If you need to obtain custom assembly services for harnesses and cables, contact us now for a quick quote on wire harnesses and cable assemblies, or contact us by email sales@kingpcb.com.