5 Common Issues About Connectors in Custom Wire Harness

We understand the inherent frustration that comes with choosing the right cable assembly, which is why we take out the entire process of choosing your cable assembly. Instead, we create the cable assembly that you want the way you want it.

Our custom cable assemblies have better wiring and insulation than off-the-shelf cable assemblies. You can choose the connector that you want throughout your cables; you can also choose the material of the wiring itself. We test out wires for the best performance that you can buy, ensuring that the custom cable that you are buying is the best around.


A vital issue with low-quality wiring harnesses is the “push back” of wires of contact retention. There are different options available for connectors like insert-able contacts and crimp on. If you are facing power failure due to ongoing issues with connectors, you need to try custom wire harness.

Wire Harness Connector
Wire Harness Connector

For high standard custom wire harnesses, CLOOM Tech designers deploy quality connectors. The intricate designs of custom wire harness highly depend upon the connectors. Custom wiring harnesses with premium connectors and terminals can prevent these issues, let’s take a look.

1.Custom Wire Harness–Unprotected Contacts

Contacts are critical for the successful working of the connector. Unprotected connections can initiate corrosion that will not only affect the current supply but will lead to supply failure later on. Connectors in custom wire harnesses fail due to poor contacts. Contacts consist of small metal parts and pins that imitate the current flow in the harnesses.

As these metal pins are smaller in size hence are more vulnerable to moisture, corrosion, and other external factors. These contacts for custom wire harness connectors come with a limited lifespan. The continuous use without proper layout will lead to premature failure of the connections and connectors. Contact must have an appropriate coating and protective layers for improved quality.

Automotive male and female connectors
Automotive male and female connectors

Poor quality contacts will exhibit a “push back” phenomenon too. Whenever you insert the references in the right cavity, due to poor quality, it will push back the contacts. Due to a broken circuit, connectors will interrupt the power supply. These things must be under consideration while testing connectors and wire harnesses for practical applications. CLOOM Tech engineer not only uses premium quality materials for the contacts, but they also put contacts and connectors under rigorous testing. Every product that we ship to our client comes with the approval of our testing department. State of the art testing labs and strict quality standards help us to meet user demands and expectations in a better way.

2. Custom Wire Harness–Poor Crimping Techniques

Crimping is the most common way to create a connection between wires and terminals or connectors. For the electrical supply, connectors need to join different cables in a cable assembly or wire harness design. Crimping referred to as the process of connecting wires to the connectors or terminals by using special techniques and tools. The name of the method suggests that a bond is created for different wires by compressing connectors on the wire. You don’t need to perform any kind of complex soldering process to connect two wires or connectors.

In the case of poor crimping technique or use of the low-grade tool, the connector will not hold the wire firmly. As there will be enough space for the moisture to penetrate on the joint, it will initiate the corrosion in the joints. Decay is one of the biggest threats to the safety and efficiency of custom wire harnesses. As the decay starts covering the links, it can result in power supply failure. Most of the time, decay can lead to short circuits too. So, we ensure that we follow the international crimping tools and crimping standards for the best quality connectors for the custom wire harnesses.

An engineer performing crimping on wires
An engineer performing crimping on wires

3.Custom Wire Harness–No Strain Relief

Strain relief is critical in connectors for custom wire harnesses. No strain relief can lead to a connector breakdown during any kind of mechanical movement. Low-grade custom wire harness teams tend to overlook the importance of strain relief. Hence, a small missing mechanical property of connectors can cause total power failure.

Enough strain relief for the connectors allows the flow of force in any direction due to mechanical movement during the installation of working. Due to a lack of strain relief, the wire can push back from the terminal or the connector. A lot can go wrong with connectors in custom wiring harnesses, and lack of enough strain is one of those issues.

Strain relief for wire harness connectors
Strain relief for wire harness connectors

You will have to choose custom wiring harness manufacture that uses professional tools for accurate design layout. Precise design and layout of the wire harness will ensure the balanced strain relief to transfer force due to movement. Extra strain relief will also create problems as the wires may not stay firmly tight with the connectors. With the loose wires in connectors, sooner or later, the system will collapse.

4.Custom Wire Harness–Poor Wire Harness Layout

From the vehicle industry to the aerospace sector, custom wiring harnesses have become an essential part of almost every field. The increasing demand for custom wire harnesses requires the manufacturers and designers to work on something extra and something unique. The electrical routing in the wiring harnesses highly depends upon the quality of connectors. Intricate wiring harness designs and layouts may require exceptional connectors. The limited space and weight reduction can affect the performance of the connectors in custom wiring harnesses.

As the design does not meet the project specification, continuous alterations in the connectors will damage the contacts. The contacts are tiny metal parts that cannot take much abuse. Hence, the changing requirements of the project lead to loos contacts. If the custom wiring harness is up the mark according to the project specifications, you won’t have to undergo the stressful modifications in the harness design.

Quality of the wiring for cars at a modern plant
Quality of the wiring for cars at a modern plant

As the harness layout changes, connectors may fail to deliver the desired results in the new design. A professional custom wiring harness manufacture will get the layout right in the very first stage. More revisions and modifications mean less lifespan of the connectors due to poor contacts. CLOOM Tech custom wire harness team especially emphasizes the importance of the design process. Without getting the designing part right, you cannot scale your project. Accurate and precise design is the backbone of the custom wiring harness process.

5.Custom Wire Harness–Missing Hardware

Just imagine that contacts are gone missing during the shipment or the installation process. This situation is the ultimate failure of the whole wire harnesses. A custom wire harness is a unified whole, which means that every part matters equally for the success of the entire project. Although Connectors are usually small in size yet even if single contact is missing, that joint won’t be operational. Poor crimping can loosen the wires, and if the connector goes missing due to poor crimping, you will have to repair that joint. If you want to avoid any of the given problems with custom wire harness connectors, then focus on every component of the harness.

Assemble wire harness, electrical wire
Assemble wire harness, electrical wire

Dealing With Contact Retention Failures

Once you have inserted the contact in the cavity, it should stay there so that the current can continuously flow through the circuit. If the connection is loose, then it can push back with breaking the course. In the worst situation, contact retention can lead to short courses too. These small connectors and terminals can sabotage the whole project. Especially in the automotive sector, connectors are the most important. Detecting and repairing the damaged connector due to contact retention failure can be a hectic task. Here are some ways to deal with contact retention failure for custom wire harness.

• Push-click-pull

It is a really simple yet effective method where you don’t need to use any type of complex tools or equipment. Make sure that you don’t apply too much force as there are no specific standards for the method. Pushing or pulling the wire with additional force can break the joint. So, there is a lot of human error involved in this method.

• Verify using tools

This method use tools to verify the retention of the contacts in the connector. You can measure the force applied for the connections, and these tools are not expensive. Although this method based on the application of tools and equipment for verifying the retention, yet it can be costly in terms of labour cost. Your technicians will have to verify each pin against testing tools. Errors may occur after the assembly process instead of during the assembly.

• Electrical testing

It is the fastest way to verify contact retention by using the advance electric method. Electric tools can analyze almost everything that can go wrong with the connectors. Instead of testing one by one, a complete batch of contacts can undergo the electric testing process.


Even with all of these precautionary measures, inadequate quality wire harnesses will ditch you at some point. The best way is to invest your money in the services of a professional company. CLOOM Tech not only detected these issues with connectors in custom wire harnesses, but we also resolved these issues. If you want high-quality custom wire harnesses with reliable connectors, CLOOM Tech is the best custom wiring harnesses manufacturers in China.

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