Honda and Nissan have officially confirmed a new collaboration focused on the software and electronic systems underpinning next-generation vehicles, extending cooperation between the two Japanese automakers after their widely discussed merger plans ultimately fell apart.

Honda and Nissan Sign Joint Development Agreement

Late in 2024 and early in 2025, Honda and Nissan appeared to be moving toward a merger. Although that deal did not materialize, the companies have remained cordial and continued discussing other potential areas of collaboration, including larger SUVs.

Recent reports suggested the automakers were working together on software, and both companies have now confirmed the partnership. Honda and Nissan said they have “entered into a joint development agreement to standardize multiple electronic control units (ECUs) that form the core of next-generation software-defined vehicles (SDVs), along with the in-vehicle operating system and key parts of the middleware, and vehicle control software that run on these ECUs.”

New Technology Planned for Vehicles From Fiscal Year 2029

The electrical and electronic architecture being jointly developed is expected to be integrated into both automakers’ next-generation vehicles beginning in fiscal year 2029.

The collaboration focuses on technology that will play an increasingly important role in how buyers perceive and interact with more digital vehicles. Developing the underlying software and electronic structures required for those vehicles is also expected to be costly.

Under the agreement, Honda and Nissan will establish common specifications for multiple core and zone ECUs used in next-generation software-defined vehicles.

Why Zone ECUs Matter for Next-Generation Vehicles

As seen in Neue Klasse BMWs, zone ECUs function like centralized processing units that group electronics and wiring according to their physical location in a vehicle, such as the front, middle, rear, left side, or right side.

This approach can shorten wiring lengths, improve manufacturing efficiency, reduce weight, and increase communication speeds. Zone ECUs also provide greater software control, making it easier to upgrade vehicles over the air without requiring new hardware.

With fewer individual ECUs and fewer wiring connections, there are also fewer potential failure points. Faster communication and improved software control make zone ECUs particularly suitable for advanced driver-assistance features, including semi-autonomous driving.

Honda and Nissan Aim to Share Costs and Expertise

As with many automotive collaborations, the partnership gives Honda and Nissan an opportunity to split development costs and share expertise.

The companies are also seeking to “accelerate progress toward carbon neutrality and help realize a future with zero traffic fatalities involving their vehicles,” with the latter goal also shared by Volvo.

As Chinese vehicles continue setting new standards for electrified models and their capabilities, Honda and Nissan hope that sharing development efforts will strengthen their competitiveness.

Partnership Could Support ProPilot and Asimo Development

Discussions between the two companies have been underway in Japan since 2024 and are now scheduled to produce results two years later than originally planned.

The collaboration could support Nissan’s push to deploy ProPilot driver-assistance technology and Honda’s efforts to integrate its Asimo operating system into a wider range of vehicles.

Unlike partnerships centered on shared powertrains or chassis systems, the agreement is designed to allow Honda and Nissan to maintain their individual identities while introducing a common electronic architecture aimed at competing with global leaders in software-defined vehicle innovation.