Proposal to amend GTR 25 by modifying requirements for State-of-Certified Energy (SOCE) monitors, battery performance, and in-use verification procedures for heavy-duty electrified vehicles. The amendment refines test procedures for usable battery energy determination through four methods (Methods 1a, 1b, and 2, and an alternative chassis dynamometer method), updates measurement requirements and accuracy specifications, clarifies vehicle selection criteria during certification and Part A verification to establish worst-case configuration by highest UBE value, increases temperature tolerance during test soak to 7°C for improved applicability, revises Annex 2 to reflect additional regional regulatory requirements, and improves descriptions of test methods to enhance applicability and accuracy of results. Implementation occurs following entry into force as specified in regional provisions.