Vehicle Feature Activation in Software-Defined Vehicles Based on a Conceptualization of Vehicle Lifecycle Upgrades

The transition toward software-defined vehicles (SDVs) enables vehicle functionality to evolve beyond production through software-driven mechanisms. Despite growing industrial adoption, industry sources differ in the terminology and scope used to describe this phenomenon. Whether the scientific literature provides a common conceptualization of feature activation after vehicle production remains unclear. A systematic literature review of five scientific databases was conducted in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA 2020) guidelines, followed by an integrated analysis of the identified concepts, terminology, and definitions. The results reveal substantial conceptual and terminological fragmentation, with existing studies describing the phenomenon from multiple partially overlapping perspectives rather than providing a unified definition. Based on these findings, a hierarchical conceptual model of vehicle lifecycle upgrades is proposed, distinguishing between internal vehicle upgrades, realized through software-based mechanisms on existing hardware, and external vehicle upgrades, requiring the integration of additional physical components. This distinction provides a conceptual foundation for delimiting software-enabled feature activation from hardware-based vehicle evolution. Furthermore, the proposed framework positions vehicle lifecycle upgrades within the SDV paradigm and establishes a basis for future research, industrial communication, and the systematic classification of software-enabled vehicle evolution.