Honda Motor, Nissan Motor and Mitsubishi Motors are reportedly in advanced negotiations to standardise electronic control units (ECUs) across their next-generation vehicle line-ups, reported Nikkei Asia.

The companies are looking to pool procurement of the components to bring down costs and sharpen their edge against Chinese rivals and Tesla.

The ECUs being discussed are central to software-defined vehicle (SDV) capabilities, covering functions such as autonomous driving and in-vehicle information systems.

Honda and Nissan have a few outstanding conditions to resolve, though both sides are targeting an agreement within weeks, the report said.

Vehicles incorporating the jointly sourced units could enter the market between 2029 and 2030, with hybrid models under consideration alongside electric ones.

Mitsubishi is expected to make a financial contribution to the arrangement, with procurement and development terms to be confirmed at a later stage.

Beyond ECUs, Honda and Nissan are separately in discussions to align their onboard operating systems - a foundational layer of SDV architecture - and are also working towards a joint manufacturing agreement in North America.

A potential production-sharing structure would see Nissan supplying pickup trucks to Honda and Mitsubishi, with all three parties also exploring co-development of larger vehicles.

The two larger automakers first announced plans to examine a software partnership in the fiscal year ended March 2024, following which they undertook joint foundational research.

Merger discussions that began in December of that year broke down in February 2025, after which both companies opted to assess collaboration on a project-by-project basis rather than pursue a full corporate tie-up.