Episode 02
When the Vehicle Gets a New Nervous System
Reading Time: 4 Minutes
WHY THIS MATTERS
- Zonal architecture consolidates vehicle inputs and outputs around physical zones, reducing dependence on increasingly complex distributed electronics.
- Wiring harness complexity is becoming a strategic issue, particularly as vehicles accumulate sensors, actuators and software-controlled functions. McKinsey estimates wiring harnesses can represent around 20% of an automotive E/E architecture budget.
- High-speed automotive Ethernet and centralised computing are emerging as critical enablers of the new architecture.
- Zonal architecture could provide a stronger hardware foundation for software-defined vehicles, OTA updates and cross-domain functionality.
- The transition is evolutionary rather than instantaneous: legacy distributed and domain architectures will coexist with zonal systems for years.
EDITORIAL REFLECTION
“Every generation of mobility has redesigned the way power and information travel. The next generation may redesign the vehicle around the movement of data itself.”
THE VEHICLE'S NEW NERVOUS SYSTEM
Look beneath a modern vehicle and you will find something remarkable. Not just an engine, battery or electric motor, but a vast network of sensors, controllers, actuators, communication links and electronic systems constantly exchanging information. A vehicle can have hundreds of electronic functions, each demanding power, processing and communication.
The problem is that this digital growth has been accompanied by something much less glamorous: wiring.
As vehicle functions multiply, so do cables, connectors, control units and communication pathways. The electrical architecture becomes progressively harder to design, manufacture, diagnose and update.
Zonal architecture proposes a different way of organising this complexity. Instead of designing the vehicle primarily around individual functions or domains, the architecture groups inputs and outputs according to where they are physically located. The vehicle begins to think in zones.
FROM MANY BRAINS TO A NETWORK
Traditional vehicle architecture evolved organically.
- A new function arrived.
- A new ECU was added.
- Another sensor appeared.
Another communication connection was required. Over time, the vehicle accumulated an intricate electronic nervous system. Domain architectures subsequently consolidated functions such as powertrain, body control or ADAS into larger computing domains.
Zonal architecture takes another step. Sensors and actuators remain distributed around the vehicle, but local zonal controllers increasingly aggregate their inputs and outputs. High-speed networks then connect those zones to powerful central computing platforms.
The conceptual transformation is:
Distributed ECUs → Domain Controllers → Zonal Controllers + Central Compute
It is not simply a reduction in boxes. It is a change in the architecture of information.
THE WIRING HARNESS BECOMES THE STORY
For years, wiring harnesses were largely invisible to the vehicle buyer. Yet they are becoming increasingly important to vehicle engineers.
A modern harness carries power and data across the vehicle, often following complex routes between components and controllers. As functions multiply, that complexity creates weight, packaging challenges, manufacturing difficulty and cost. McKinsey estimates that wiring harnesses can account for approximately 20% of total E/E architecture budgets, illustrating why reducing their complexity has become strategically significant.
Zonal architecture moves controllers closer to the components they serve. That can shorten local wiring paths while replacing many point-to-point connections with a higher-speed network backbone. Research published in 2025 found that increasing the number of zones in a vehicle architecture can reduce wiring length and complexity in its case study.
The objective is not simply less wire. It is less architectural complexity.
WHEN DATA TRAVELS DIFFERENTLY
The zonal vehicle increasingly resembles a computer network. Local devices connect to nearby zone controllers. Those controllers communicate across a high-speed backbone. Central computing platforms process information and coordinate vehicle functions.
Automotive Ethernet is becoming an important technology in this transition, with industry architectures looking towards high-speed links for communication between zonal controllers and central computing resources. TE Connectivity, for example, describes future zonal architectures using high-speed Ethernet links between port-dense zonal nodes and high-performance computing platforms.
The implication is profound. The vehicle's electrical architecture begins to look less like a collection of independent electronic systems… and more like a distributed computing platform.
THE FOUNDATION FOR SOFTWARE-DEFINED MOBILITY
This is where zonal architecture connects with the larger transformation of the automobile. A software-defined vehicle needs software to communicate across multiple vehicle functions without being constrained by a maze of tightly coupled hardware.
Zonal architecture helps separate where computing happens from where sensors and actuators are physically located. That separation can make vehicle functions more modular and potentially easier to update, integrate and scale. Recent research describes the combination of central high-performance computing and zonal I/O aggregation as an important architectural foundation for SDVs.
But there is an important distinction. A zonal vehicle is not automatically a fully software-defined vehicle. Zonal architecture is an enabling foundation. The software layer, middleware, computing platform, networking, cybersecurity and OTA infrastructure must work together before the full SDV proposition can be realised. That distinction matters.
THE COMMERCIAL VEHICLE CONNECTION
The implications extend well beyond passenger cars. Commercial vehicles are particularly sensitive to wiring complexity because they combine long vehicle dimensions, multiple electronic subsystems, body equipment, trailers, sensors and increasingly sophisticated fleet technologies.
A 2026 research collaboration involving the Technical University of Munich and Daimler Truck specifically identifies wiring-harness length and weight as a significant challenge in the cost-sensitive commercial vehicle sector, where total cost of ownership is critical.
For trucks and buses, zonal architecture could therefore influence more than electronics.
It could affect:
Vehicle weight → Energy efficiency → Packaging → Diagnostics → Manufacturing → Maintenance → TCO
That makes zonal architecture a potential commercial-vehicle story, not merely a passenger-car technology trend.
THE TRANSITION WILL NOT HAPPEN OVERNIGHT
The technology is promising, but the transformation is complex. High-performance central computers must meet demanding functional-safety requirements. Networks must deliver predictable performance.
Cybersecurity becomes even more important as more functions converge onto fewer computing platforms. Software architectures need to become modular. Legacy systems cannot simply disappear. And manufacturers must manage the transition across vehicle generations, supply chains and production facilities.
Recent SAE research emphasises precisely this point: the industry is moving towards zonal architectures, but central compute, zonal controllers, high-speed Ethernet and standardised software architectures are still maturing. The future is therefore not a sudden replacement of one architecture by another. It is an architectural evolution.
BY THE NUMBERS
20%
McKinsey's estimate of the share of an automotive E/E architecture budget that wiring harnesses can represent.
18%
McKinsey's projected global share of vehicles with zonal architecture by 2030 in its 2023 analysis. This is a forecast, not a current adoption figure.
30–40%
McKinsey's projected annual growth range for the combined market for domain, zonal and central compute units between 2023 and 2030.
10 Gbps
A high-speed Ethernet data rate cited by TE Connectivity for inter-zonal communication in next-generation E/E architectures.
16 nm and below
Process-node range cited by McKinsey for emerging SoCs used in zonal controllers in its analysis.
Forecasts and company/industry estimates are identified as such and should not be interpreted as universal production benchmarks.
emBRWace PERSPECTIVE
For decades, vehicle electronics evolved by addition.
A new function meant another controller, another connection and another layer of complexity.
Zonal architecture proposes a different philosophy: organise the vehicle around where information originates and where action is required, while moving more of the intelligence into central computing. It is not simply about reducing cables. It is about creating an architecture capable of supporting a vehicle that can evolve through software.
The transformation is still underway. But if the vehicle of yesterday was defined by its mechanical architecture, and the vehicle of today increasingly by its electronic architecture, the vehicle of tomorrow may be defined by the relationship between its computing, software and data.
THOUGHT TO TAKE AWAY
The vehicle is acquiring a new nervous system. Zonal architecture may be the bridge between today's electronically connected machine and tomorrow's continuously evolving software-defined vehicle.
NEXT ON FUTURE OF MOBILITY
Episode 03
SOFTWARE-DEFINED VEHICLES
When the Vehicle Becomes an Upgradeable Platform
The next chapter explores how centralised computing, vehicle operating systems, cloud connectivity and over-the-air updates are changing the very definition of a vehicle—from a finished product to a platform capable of continuous evolution.
Coming Soon…
MOBILITY ANSWERS
1.What exactly is zonal vehicle architecture?
Zonal architecture organises a vehicle's electrical and electronic functions primarily according to physical location. Sensors and actuators connect to nearby zonal controllers, which communicate with central computing platforms through high-speed networks. This differs from traditional architectures where individual functions often have dedicated electronic control units and complex point-to-point wiring.
2.Why does zonal architecture reduce wiring complexity?
By placing controllers closer to the components they serve, zonal architecture can shorten local wiring routes and consolidate many connections. Instead of running separate long cables between numerous devices and controllers, information can travel through a structured network backbone.
3.Is zonal architecture the same as a software-defined vehicle?
No. Zonal architecture is an enabling hardware and networking architecture for many software-defined vehicle designs. A full SDV also requires suitable computing, software architecture, middleware, cybersecurity, data infrastructure and update mechanisms.
4.Why is automotive Ethernet important?
Zonal architectures require high-speed communication between local controllers and central computing resources. Automotive Ethernet provides substantially greater bandwidth than many legacy in-vehicle networks and is therefore becoming an important part of next-generation E/E architectures.
5.Will zonal architecture benefit commercial vehicles?
Potentially, significantly. Commercial vehicles have long wiring routes and increasingly complex electronic systems. Reducing wiring complexity, consolidating computing and simplifying diagnostics could affect vehicle weight, manufacturing, maintenance and total cost of ownership. Research involving Daimler Truck and the Technical University of Munich specifically identifies these potential benefits for commercial vehicles.
