Wiring faults on heavy goods vehicles are some of the most time-consuming electrical problems to diagnose — and on a 7.5 ton cab-over truck, accessing the engine bay wiring loom means tilting the cab. That’s exactly what this job involved, and our mobile auto electrician was on-site to trace, diagnose, and repair the fault without the vehicle needing to go anywhere near a workshop.
The Job: Wire Fault on a 7.5 Ton HGV
The customer had an intermittent electrical fault on their 7.5 ton cab-over HGV — the kind of fault that can cause warning lights, starting issues, or loss of function on specific systems, and which is notoriously difficult to pin down without the right equipment and experience.
Our first step was tilting the cab to gain access to the engine bay and the main wiring loom. With the loom fully exposed, we were able to carry out a systematic fault trace — working through the harness section by section to identify where the break or damage was located.
Fault Found and Repaired On-Site
Once the fault was traced to the affected section of the wiring harness, we carried out a clean, professional repair on-site. The damaged wires were cut back to good material and rejoined using quality inline connectors — ensuring a reliable, durable repair that restores full electrical continuity.
No towing to a workshop. No waiting days for a slot. The truck was back in working order the same day.
Why HGV Wiring Faults Are Best Diagnosed by a Specialist
HGV electrical systems are significantly more complex than those in cars or vans. The wiring looms are longer, they pass through more connection points, and they’re often exposed to higher levels of heat, vibration, and moisture over the life of the vehicle. Common causes of HGV wiring faults include:
- Chafed or worn insulation — wires rubbing against bodywork or engine components over thousands of miles
- Corroded connectors — especially in areas exposed to road salt and moisture
- Heat damage — wiring routed too close to the exhaust or engine
- Previous poor repairs — bodged splices or wrong-gauge wire causing recurring faults
- Rodent damage — mice and rats chewing through loom insulation, particularly in stored or infrequently used vehicles
Proper fault tracing — using circuit diagrams, multimeters, and oscilloscopes where needed — is the only reliable way to find the root cause rather than just chasing symptoms.
We Come to You — Mobile HGV Auto Electrician
Getting a 7.5 ton truck to a workshop isn’t always practical — especially if the fault is affecting drivability or the vehicle is loaded. As a fully mobile auto electrician, Just Autos comes to your yard, depot, home, or wherever the vehicle is located across Nottinghamshire, South Yorkshire, Derbyshire and surrounding areas.
We carry a full range of diagnostic equipment and electrical repair materials, so the vast majority of faults can be diagnosed and repaired in a single visit. We work on:
- 7.5 ton HGVs — cab-over, box vans, curtainsiders, tippers
- 18 tonne and above — articulated trucks, rigids, flatbeds
- Refrigerated vehicles — including fridge unit wiring faults
- Plant and machinery — JCBs, telehandlers, forklifts, dumpers
- Vans and LCVs — all makes and models
Got an electrical fault on your truck or commercial vehicle?
📞 07903 378954
✉️ info@just-autos.uk
🌐 www.just-autos.uk
Mobile auto electrician covering Nottingham, Mansfield, Worksop, Newark, Retford, Sheffield, Doncaster, Chesterfield and surrounding areas.
