Harnessing Power: All About Wiring Harnesses

The wiring harness is the measurement of quality that all vehicle builders are held to. Building a good wiring harness is not that difficult, but it does take time and requires patience—something that is easily overlooked when you have access to quick fixes like butt connectors, splice crimps and electrical tape.

How do you go from rat’s nest to loom? It is easy and consists of four components.

1. Soldering Iron
2. Heat-Shrink Tube
3. Anti-Abrasion Sheath
4. Weather Pack or Deutsch Connectors

The biggest leap in building your own wiring harness is soldering your connections and splices together. A crimp connector is easy to do, but it can have connectivity issues and can slip. Soldering is forming a chemical bond between the wires and ensures a lasting, flexible connection. Twisting two wires together, and then soldering their connection followed up by covering them with heat-shrink gives you a connection that will last the tests of time. The best heat shrink tube is marine grade tubing that has heat activated adhesive on the inside. The adhesive forms a water barrier to keep moisture out of the splice and also helps keep the connection secure.

An anti-abrasion sheath is a nice visual touch, keeps the wires together and makes sure that the insulation of the wire is not exposed to the elements or any possible sharp areas. Weather Pack and Deutsch Connectors allow you to disconnect electrical accessories from the harness and form a waterproof barrier for the connection so that corrosion or dust intrusion is not an issue and your reliability is maximized.

We built this harness using Weather Pack connectors, marine grade adhesive, heat-shrink tube and anti-abrasion sheath all purchased from McMaster-Carr. It uses 18-gauge wire and will be a throughput from our 4x4sPOD source to a set of auxiliary lights on the front bumper of this vehicle.

So, while the wiring harness might not be something anyone sees, taking pride in what you made is just as satisfying as a compliment, and you have ensured a quality connection to your accessories. Plus, think of the bragging rights when you pop your hood.