Five-Star Manufacturer
Fast Delivery
Customized Service
HomeTips & GuidesCustom wire harness assembly: A complete guide on finding a wire harness manufacturer.

Custom wire harness assembly: A complete guide on finding a wire harness manufacturer.

About Custom wire harness assembly, All equipment, machinery, or electric control panels function due to the wires and cables inside them. These electronic devices have a complete web of wires and cables. 

Imagine what will happen if one has to route these wires and cables individually.

It will become time-consuming and laborious.

The best solution is to create the assembly of wires and cables outside the equipment and then install it once the equipment is ready. This ready-to-install assembly of wires and cables is an electrical wiring harness.

This article discusses a custom one and helps you find your manufacturer.

What is a wire harness?

Also known as wiring assembly and cable harness, it is a group of cables, wires and sub-assemblies. 

They all together help to transmit electrical power or signals. You can find at least three different components in a basic wire harness. 

In contrast, a classic or complex harness may have more wires and other potentially active or passive components.

Wire harnesses vs. cable assemblies:

Often, you refer to a wire harness as a cable assembly and vice versa, as their purpose looks the same. 

However, there are some differences between these two in terms of their use and manufacturing process.

KeysWire harnessCable assembly
Shape Here, you can find multiple branches running in different directions, with multiple terminations at each branch.Here, generally, there are two ends only.
Industrial applicationsFound in electronic, automotive, aerospace, military, automation machines, robotics and consumer products.Mainly found in construction, IT, medical machinery, and telecom equipment.
Options at CloomMilitary wire harnessHoop-up wire harness (low voltage)Automotive wire harnessPower cablesData cablesCoaxial cable assembliesRibbon or flat flexible cables
PurposeA cost-effective solution to organize wires,  ensuring electrical connectivity between different systems in an assembly.Cable assemblies mainly enable external connection to the equipment and can withstand different environmental conditions. 
Services at CloomWire harness assembly with or without terminations and connectors; Testing of individual harnesses; Ultrasonic welding; Ribbon-style wire bonding; Pre-cutting, stripping, twisting, and termination of individual wires; Labeling of wire harness; Wire harness ranging from 26-10,000mm in length and 30-8 AWGCable overmolding; Cable ties; Cable lacing; Heat-shrink covering; Customized colors; Customized labeling and color coding; Individual tags; Independent circuits Ink stamping (four colors)
Cable assemblies 

Cable assemblies 

How to build a custom wire harness assembly

The manufacturing of the wiring harness includes the following steps:

Step 1: Design

Every wire harness uniformly transmits power or information. It is essential to get a customs ensign ready for the electronic parts to overcome problems related to any potential electrical issues in the future.

 Once the design for the electronic parts is ready, it becomes easy to manufacture wire harnesses step by step. 

At this stage, engineers also choose the components required in the manufacturing. 

Step 2: Prototyping

In this step, engineers or technicians test the real-life sample of their final product and test it for its intended application. 

It helps them to make changes before the first production run to check optimal performance.

Step 3: Production and assembly

To ensure the best performance, a wire harness assembly must meet all design specs and high-quality standards with minimal errors. 

Though automation has become integral to all manufacturing sectors, wire harness manufacturing still uses manual efforts. 

It is not only cost-effective but also ensures the completion of intricate processes with high precision but, of course, takes more time.

Another reason manufacturers prefer manual assembly is to customize each wire harness for its intended application.

 A wire harness is a specific part of any electronic product, and it must meet its electrical and geometrical problems with its design and functionality. 

These must fit within the electrical product along with other components and wires.

 Further, wire harnesses must protect products from damages (internal and external) that arise due to chemicals, moisture, and crossed wires.

Wire cutting:

The first step in manufacturing wire harnesses is to cut wires at the right length through wire-cutting equipment.

Stripping and making connections:

Next, the engineers strip the cut wires to expose the cores. The terminals and connectors are attached to the exposed cores. 


Finally, on an assembly board, engineers assemble all the wires to make an assembly. 

The process includes routing the wires through sleeves, applying fabric tapes, adding terminals (use crimping tools to crimp terminals and soldering iron to seal wire ends), and inserting sleeves into another for fastening strands through cable ties, clamps, or tapes.

Step 4: Testing:

Even after the prototype testing, all the wire harnesses undergo electrical safety testing after production. 

Technicians check their working conditions to ensure their 100% performance.

Assembly wiring harness

Assembly wiring harness

Benefits of outsourcing the custom wire harness assembly:

These days, electrical equipment manufacturers outsource the manufacturing of wire harnesses and cable assemblies. 

Here are some benefits that show you why outsourcing is a better option.


A dedicated wire harness manufacturer will, of course, have years of experience in manufacturing wire harnesses quickly and with extreme precision.

Lesser production costs:

Outsourcing the production of wire assemblies to a low-cost country like China saves money on production costs, labor costs, and other overheads.

Better production capability:

Outsourcing the manufacturing of wire harnesses allows you to invest your money, time, and resources in producing products in large volumes. 

More capital for business investment:

Outsourcing wire harness manufacturing saves you from this cash crunch so that you can focus on other prominent business areas.

Sourcing low-cost raw materials:

China’s wire harness manufacturers can source raw materials at much cheaper rates than you. 

When these manufacturers get discounted raw materials, they store them in bulk. 

Thus, with such manufacturers, you can be sure of getting large volumes of wire harnesses and assemblies as and when required. 

Also, these discounted prices help you get products from them at cheaper rates.

The flexibility of choosing different manufacturers:

When you outsource the manufacturing of wiring harnesses, you have more options than if it had been in your step.

 You can outsource manufacturing to different manufacturers based on design and other requirements.

 It’s better to have expertise in that field if you are working on different designs, as they will have the required equipment.

Tips to qualify your custom cable harness manufacturers to ensure long-term and successful contracts:

Wire harness manufacturing is a complex process, and you must discuss all specifications and minute details with your CM before making a deal.

 Here are some equations that you must ask your CM to see if they qualify for this job.

Does the CM have the proper equipment?

If the CM follows the manual production process, you won’t benefit much after hiring as they will charge high labor costs. 

Ensure the CM has the modern equipment for a fast production process.

 With proper equipment, you can be sure of getting precisely cut wires, clean insulation removal and other highly accurate accomplished tasks.

Do they promise quick delivery time?

Timely delivery of the products is essential to win your customer’s trust. Ask your CM if they can handle large productions in a limited time. 

Some vendors follow specific strategies like blanket orders, buffer quantities, Kan-Ban systems, and consignment inventory for fast deliveries.

Make sure that you discuss all this before you hire them.

Do they follow ISO 9001 high-quality procedures and standards?

The international standards organization ISO 9001 ensures that companies follow specific procedures to provide good quality products and use continuous improvement processes in manufacturing.

 If a CM already follows ISO 9001 standards, they must be continuously vigilant about quality and safety issues.

Can they offer advantageous payment terms?

Purchasing products on terms means you can pay the invoice after 30 days of product shipping. You also get a discount for early payment.

You can ask for payment terms if you have more business with the manufacturer.

Does the CM accept blanket orders?

In blanket orders, you can order for more but get shipped fewer products per month and pay for that only. 

For example, you ordered 1000 pieces but want to get only 250 per month and pay for that particular quantity. 

In this way, you commit to buying 1000 pieces without being burdened by paying it in one go. 

Also, the manufacturer can prepare himself by managing his inventory in bulk for monthly orders.

Are they capable of producing buffer quantities?

If your requirements are for fast deliveries, your CM must be able to produce and hold buffer quantities. 

It also comes in handy on-demand fluctuation. Suppose your normal monthly requirement is 1000 pieces, but if your CM can produce buffer quantities, you can order 1300 pieces.

 You will pay for 1000 pieces shipped, and your CM will keep 300 pieces on the shelf, ready to ship on your order.

Does your CM offer discounts for bulk orders and free shipping?

Every opportunity to save money is vital in business. Before selecting a CM, you should enquire about the order threshold to gain free shipping. 

You should ask about the discounts offered on bulk orders. If such order quantity is easy to meet, you can realize substantial savings in doing business with such a CM over time.

Do they offer customized products as per your specs?

You should always ask your CM whether they can offer cables and wires in lengths and cuts as per your specific requirements. 

You should check their quality control systems to see whether or not they will be able to meet your quality requirements. 

They should be able to produce their written quality control and quality assurance documents on demand. 

Also, enquire whether they can offer additional services, such as dipping, soldering, cable termination, etc., that are within the tolerance limits of your specifications. 

All factors, such as cost, quality, delivery, and payment terms,m should guide your final decision to choose any CM.

Custom wire harness and cable assemblies manufacturing process at Cloom:

We follow a standard process while building the required wire harness.

Ask for a list of information from you

  • Bill of material, including part numbers
  • Connector images showing pin locations
  • List of wires specifying nets, wire colors, and connector pin-outs
  • Drawing of full assembly mentioning labeling locations, tolerances, and assembly instructions
  • Final harness test specs

You must know that the more detailed and precise the information you provide, the fewer problems we will face during the assembly process.

Design review

First, we will review the (BOM) bill of materials and other documents. 

The BOM will have all the information regarding materials and instructions required to manufacture a product. 

We will also examine the cost, performance, and availability of all mentioned materials and suggest any possible replacements.

Preparation of materials:

Once the BOM is final, we start purchasing and accumulating all the materials and components required for production.

Assembly documentation:

Based on your insights, we will create assembly documentation required on the manufacturing floor. 

This documentation has all the detailed steps, test procedures, images, and illustrations. Further, we will also create an assembly panel with all needed pegs at specific locations.

Wire harness production:

After all the preparations, the production process starts. 

Quality assurance:

Once the wire harness assembly process is completed, it undergoes the testing phase, which checks its manufacturing quality, labeling, and efficiency to fit the system.


Wire harnesses and cable assemblies are integral to any electronic equipment, and you must maintain their quality and specifications. 

Always look for a reputed manufacturer for your wire assembly needs. 

Cloom is a leading wire harness manufacturing company in Asia with a modern setup, latest tools and equipment, and thorough knowledge and experience. 

We offer customized services for wire harnesses in small equipment or large machinery.

I am Lillian Yang, having been a sales manager for over 10 years.

I have received many positive reviews from customers. They have praised our excellent service, on-time delivery, and high-quality cable assemblies.

For your projects, please provide cable assembly files/images/smples, etc., so that I can send you a quotation within 24 hours.

Contact me now and let’s get started on building your wire harnesses!

Background media

For Better Future
and Business
Let’s Talk Now!

Fill in your details and we’ll get back to you in 24 Hours.

Contact Form Demo


[email protected]




3rd Floor, Nanhai Plaza, NO.505 Xinhua Road Xinhua District,
Shijiazhuang, Hebei, China. 050057


© 2007- 2023 Cloom tech. ALL RIGHTS RESERVED.



Subscribe to our newsletter for the latest updates, exclusive offers, and exciting news delivered straight to your inbox.