Automotive Wiring Harness Assembly: 4 Important Facts to Consider

cross section of various wires and wiring harness

For modern vehicles with high-end features, single wires connecting the device to the electrical system won’t work anymore. These considerations have led to the development of complex automotive wiring harness assemblies, which are a more structured, functional and convenient way of connecting the electrical components of a vehicle.

Let’s learn more about the automotive wiring harness assembly in this blog post.

What are automotive wire harness assembly?

A custom wiring harness are a complex collection of wires, cables and connectors bundled together to form a structured device. A number of industries are using these wire harnesses to transmit signals in their electrical applications, and the automotive industry is one of them.

Automotive wire harness companies like Cloom are taking advantage of this opportunity and manufacturing harnesses to deliver optimal performance. 

An automotive wiring harness assembly is a cable assembly that can work for an automobile’s electrical system. These harnesses are designed to show compatibility with the electrical and geometric arrangements of a vehicle. 

All automobiles; be it autos, utility vehicles, trucks, three-wheelers, or two-wheelers, use automotive wire harnesses. They can be found in frames, motors or in the body of the vehicles.

wiring harness courtesy of Shutterstock

Benefits of automotive wiring harness assembly:

Plug-in installation: Bringing all the wires together in a compact and single component makes these wire harnesses more advantageous than routing and connecting single wires manually.

Reliable: Wire harnesses have a complex and tighter arrangement of wire and cables which makes them resistant to electrical circuit shorts. The capability of handling high currents and being resistant to heat and electromagnetic noise make these harnesses a perfect choice.

Durable: Consisting of long-lasting materials, they have high durability and longer life. Further, the manufacturing and installation of these harnesses ensure they withstand all types of shocks and harsh vehicle conditions while carrying power signals.

Types of automotive wiring harness assembly:

Based on circuits

Automotive wire harnesses come in different combinations of circuits, such as 12-circuit, 18-circuit, and 24-circuit. In any electrical system, a circuit is a group of one, two or more wires connected together for a specific purpose. For instance, a set of wires for the two headlights will form two circuits, while there will be a single circuit for the light, love box and starter.

How many circuits a vehicle will have depends on its electrical components, as every electrical component will require one circuit to function. It’s the electrical accessories that you have or wish to have in the future that determine the circuits in an automotive wiring harness. 

The ideal wiring harness for your vehicles will depend on the electrical system complexity, the systems you need to install, and the make and model of your automobile. However, if you wish to install some items later, you must pick a harness with a higher number of circuits. 

UnderstandingAccessories included
12-circuit wiring harnessThe most basic one, with 12-circuits indicating 12 lengths of wires for the most basic electrical accessories in a vehicle. 
Each circuit will have its designated fuse holder in the fuse block.
WipersTurn signalsRadioGaugesTail LightsParking lights Hazard flasherHeat and Air ConditionerDash lightsHornDistributorBrake lights
18-circuit wiring harnessSome vehicles have some more electrical accessories besides these basic ones, and thus, the number of circuits also increases.
In an 18-circuit automotive wiring harness, the extra 6 circuits are for
Power locksPower windowsHigh-level stop lightsElectric fanElectric fuel pumpRadio B+ memory
24-circuit wiring harnessThe 24-circuit wiring harness will add 6 more circuits for special accessories, such asUnder-hood lightLighterTrunk lightGlove box lightClockDome light:

According to position 

Engine wire harness:

As suggested by the name, these harnesses are specially designed to work for the engine compartment. The harness comprises wiring for spark plugs, fuel injectors and other engine parts.

Body wire harness:

This harness has wiring for all the electrical components in the vehicle’s body, such as sound system, lights, power windows, etc.

Chassis wire harness: 

Designed especially for undercarriage wiring, this harness has wires for sensors, taillights and other components underneath the automobile.

HVAC wire harness: 

HVAC is an abbreviated form of Heating, ventilation and Air Conditioning, and thus, the wire harness also controls systems like blower motors, AC compressors, etc.

wiring harness courtesy of Shutterstock

Choose Cloom as your automotive wiring harness assembly manufacturer:

Not all manufacturers and their products are reliable for automobile applications. How about choosing Cloom?

Rich experience:

We design and manufacture custom harnesses of all types and sizes to meet the customers’ demands and needs for modern energy markets, including:

* Appliances

* Boats

* Buses

* Agricultural equipment & implements

* Emergency vehicles

* Marine craft

* Construction equipment

* Drones

* ATVs

* Military vehicles

* Power sports

* Semi-trucks

* Small/large engines

* Generators

* Lawn care equipment

* Recreational vehicles

* Utility vehicles

* Tractor trailer chassis

* UAVs

* Golf Carts


Whether it’s a simple wiring harness or a complex device wiring, we can make it all. Our expertise lies in manufacturing-

* Sensors cables

* Coax cable assemblies

* Speciality wire harnesses

* Multi-conductor assemblies

* Battery cable assemblies


Not only designing and manufacturing, we are efficient enough to manage product validation and evaluation, quality assurance, warranty analysis and much more with great ease and accuracy.

Equipment and Technologies:

We have expertise in potting, custom over-molding and branding equipment, and thus, we can design wire harness assemblies to withstand any environmental condition, be it dirt, dust, humid, arid or desert heat.


Certified by CSA (Canadian Standards Association) and UL (Underwriters Laboratories), Cloom ensures the best quality products at the best price. 

We have many manufacturing facilities in Asia with an ISO/TS 16949-certified wire harness assembly plant in China.


With our custom wiring harness manufacturing capabilities, we are a stop solution for all your cable needs.


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