This document presents a concept for approvals of electrical/electronic sub-assemblies (ESAs) as components according to UN R155, and the installation of such approved components on vehicles already holding UN R155 approval. The proposal removes the possibility of separate technical unit (STU) approvals as a first step, limiting coverage to components connected only to power and/or reading data through approved existing interfaces. The document restructures UN R155 into three parts: Part I covers vehicle type approvals; Part II covers ESA component approvals with cybersecurity requirements; Part III covers vehicle type approvals regarding installation of approved ESAs. Requirements include cybersecurity management systems, risk assessments, threat mitigations, and reporting provisions for development, production, and post-production phases.