Maintenance Q&A – November 2023
Electrical maintenance issues are one of the worst things about owning and/or operating a vehicle. When they occur, even a simple lighting complaint can be expensive and difficult to resolve when the wiring is hidden in difficult-to-access areas of tractors and trailers.
One of the only things worse than this is paying to have an electrical repair done, only to have it experience the same issue soon after due to improper wiring repairs.
Let’s review the right way and the wrong way to perform wiring repairs so they last for the long haul.
Once a damaged wire has been located, repairing it the right way comes down to three things: stripping the wire the right way, choosing the right wire connector that will seal the connection from the elements and crimping the wire the right way.
Now, let’s take a closer look at each of these aspects of wire repair.
After the corroded or otherwise damaged wire has been cut out, it is time to strip the insulator off the good section of wire. If too much is stripped away, bare wire may extend beyond the insulator of the connector. This will inevitably allow corrosion and the eventual failure of the repair. If the wire is too short, the crimp may not hold the conductor firmly, resulting in a loose connection. This will result in high resistance, heat and melted wires. The typical strip length is five-sixteenths of an inch.
Choosing the right wire connector is critical to a long-lasting wire repair, and not all wire connectors are created equal. On interior connections, it is acceptable to use wire connectors that are not weather-sealed. But these will not survive outside your truck or trailer, especially once winter sets in. The road chemicals commonly used during icy weather wreak havoc on non-weather sealed connectors. If a connector will be used on the exterior of a vehicle, it is recommended to use a high-quality connector with sealant. When the connector is heated, it shrinks to fit the wire, and the sealant will extend out beyond the ends, sealing every nook and cranny from moisture intrusion.
The sealant does not hold the wire in place; a mechanical crimp does. The right tool to achieve this will tightly form the sleeve of the crimping area around the wire conductor without damaging the outside insulator. If the insulator is damaged during the crimp, you have created a path for moisture to corrode the wire. So be sure to choose the right size and shape crimper for insulated connectors.
With the ever-growing number of electrical and electronic components on commercial vehicles, wiring issues are inevitable. In an emergency, truck operators may have to make their own repairs. This article covers the basics, but if you need a professional to tackle your wiring problem, stop into a TA Truck Service center to have one of our highly trained technicians take a look at your rig. TA
Daniel Mustafa is the director of technical service for Travel Centers of America and Petro Stopping Centers. His role entails the research, development and implementation of truck repair services and programs. He also oversees the truck service technical support center.
He has worked in the vehicle service industry for 15-plus years and holds ASE Master Certification status in medium/heavy truck, automobile and school bus segments. He also holds ASE L1 and L2 advanced level specialist certifications and various original equipment manufacturer certifications.