US Mandates Unified Diagnostic Services for 2027 Model Vehicles

The United States is transitioning its automotive diagnostic requirements from the On-Board Diagnostics II (OBD-II) standard to a next-generation system known as Unified Diagnostic Services (UDS). While some vehicles began phasing in the technology in 2025, UDS will become a mandatory requirement for all US-bound vehicles starting with the 2027 model year.

This shift follows the long-term evolution of vehicle diagnostics. The OBD-II standard was originally mandated for 1996 model year vehicles following requirements from the California Clean Air Resources Board. This standardization was later mirrored internationally, with the European Union, Australia, and New Zealand adopting similar standards during the mid-2000s.

To support the right to repair movement, the United States Environmental Protection Agency passed the 2003 Service Information Rule. This regulation required vehicle manufacturers to provide emissions-related repair data and diagnostic tools to the general public via public websites, ensuring that the transition to more complex systems like UDS remains accessible to independent repairers.