The Challenge: Wiring Complexity Was Creating Quality and Production Risk
A leading walk-in van and truck body OEM was adding more vehicle functionality, but its traditional wiring architecture was reaching a breaking point.
As more electrical features were added to the platform, the wire harness became increasingly difficult to package, route, and assemble consistently. One of the biggest problem areas was the B pillar, where the harness had to pass through a tight structural area between the cab and cargo space. The available space was no longer enough for the amount of wiring required.
That created more than an engineering inconvenience. The crowded harness was contributing to wire chafing during installation and vehicle operation, which increased the risk of quality issues, assembly errors, and warranty claims. For an OEM building work vehicles that need to perform reliably in demanding fleet applications, those issues had a direct impact on production efficiency, field reliability, and customer confidence.
The OEM needed a better way to support growing vehicle functionality without continuing to add wiring complexity.
The Real Problem: The Architecture Had Outgrown the Vehicle
The issue was not simply the size of the harness. It was the underlying control architecture.
The existing approach relied too heavily on hardwired connections and mechanical switching. As vehicle functions expanded, each added feature placed more burden on the harness, the production team, and the available packaging space. That made the vehicle harder to build, harder to troubleshoot, and harder to scale for future options.
The OEM needed to reduce the amount of wiring routed through the B pillar while maintaining control of key vehicle functions such as auxiliary lighting, cargo lighting, dome lighting, mirror heat, fan control, and other body-related systems.
The Solution: A Distributed CAN-Based Control System
HED worked with the OEM to move from a wiring-heavy approach to a distributed electronic control architecture.
Instead of routing every function through a crowded harness path, HED helped shift control closer to the vehicle functions being managed. The system used two CL-4002 I/O modules: one programmed as the master module and one used as a client module for additional I/O. The design also incorporated CL-6024 CAN keypads with custom graphics for operator input.
That architecture allowed vehicle inputs, outputs, and keypads to communicate over the CAN bus. By moving control logic into software and distributing I/O across the vehicle, HED helped reduce the number of wires that needed to pass through the constrained B-pillar area.
The result was a cleaner, more scalable control system that reduced harness congestion while preserving the functionality the OEM needed.
What HED Delivered
HED supported the OEM with more than hardware. The project required application knowledge, architecture planning, software development, and practical implementation support.
HED provided:
- A distributed control system using CL-4002 I/O modules
- Custom application software to control vehicle functions over CAN
- CAN keypads to replace traditional mechanical switches
- A simplified wiring approach to reduce B-pillar harness congestion
- Support for key body functions including lighting, auxiliary outputs, mirror heat, and fan control
- A platform that could support future feature expansion through software and additional electronic controls
This system-level approach helped address the root cause of the OEM’s quality problem instead of treating wiring failures as isolated events.
The Results: Cleaner Wiring, Faster Assembly, and More Reliable Builds
By reducing wire harness complexity, the OEM gained a more production-friendly and serviceable vehicle architecture.
A smaller, simpler harness helped reduce routing difficulty through tight packaging areas. That made assembly more consistent and reduced opportunities for installation mistakes. With fewer wires, fewer manual connections, and more intelligence in the control system, the OEM had a stronger foundation for repeatable builds and long-term reliability.
The move to software-controlled functionality also created additional value. For example, lighting control could be managed through the system, helping address issues such as lights being left on and draining batteries. The architecture also opened the door for additional vehicle options and feature growth without requiring the OEM to keep adding complexity to the harness.
For the OEM, the impact went beyond a cleaner electrical design. The new architecture helped support:
- Reduced harness congestion in a constrained vehicle area
- Fewer wiring-related assembly issues
- Lower risk of chafing-related quality problems
- Faster, more repeatable production
- More consistent operator control through CAN keypads
- Improved troubleshooting potential through software-based control
- A more scalable foundation for future vehicle options
Why It Matters to Other OEMs
As commercial vehicles become more capable, wiring complexity can quietly become a major barrier to quality, throughput, and future product growth.
A hardwired architecture may work for a basic vehicle, but it becomes harder to manage as more features, options, and customer-specific configurations are added. More wiring means more routing challenges, more connection points, more labor, and more places for failures to occur.
HED helps OEMs take a system-level approach. By combining rugged control modules, intelligent keypads, CAN-based communication, and application software, HED helps OEMs simplify electrical architecture while building a stronger platform for future functionality.
The goal is not just to remove wires. It is to reduce complexity where it creates cost, risk, and production drag.
Build a Cleaner Control Architecture
If wiring complexity is slowing production, creating quality issues, or limiting future vehicle functionality, HED can help.
Our team works with OEMs to understand the application, identify where complexity is creating risk, and design a control system that supports cleaner builds, better diagnostics, and long-term platform growth.
Ready to simplify your next vehicle platform?
Talk with HED about building a smarter, more scalable control architecture.