RME views: Vehicles were on the road before UN R155 came into force. Retrofitting extends vehicle life in line with climate action and circular economy objectives. Retrofitters must be responsible only for components involved in the transformation and any parts they add or modify, not for original vehicle components. A risk management demonstration dossier limited to the transformed system must be included in transformation approval applications. If the origin vehicle is not R155-approved, retrofitters may provide the dossier without laboratory tests. If R155-approved, authorities decide on compliance, requiring laboratory tests if needed. Manufacturers’ data are not accessible to retrofitters. The application of cyber security provisions (i.e., UN R155 compliance) should be delayed by two years from the entry-into-force of the new regulation for the approval of EC/HFCV retrofit systems and revisions to UN R155 should also provide two-year transitional provisions before the application to the retrofit regulation.

This commented working draft establishes uniform provisions for approving vehicles of categories M and N intended to be converted into pure electric vehicles (EV) or Hydrogen Fuel Cell Vehicles (HFCV) with electric powertrain retrofit systems. The regulation covers retrofit system approval, vehicle approval, application range, installer authorization, and conformity of production. Requirements address electromagnetic compatibility, braking, power measurement, rechargeable energy storage systems, mass and dimensions, and compliance with relevant UN Regulations including UN R10, UN R13, UN R85, and UN R100. The documents includes comments from France and RME.

This Regulation provides uniform provisions for approval of vehicles of categories M₁–M₃ and N₁–N₃ equipped with electric traction chain powertrain retrofit systems to be converted into pure electric vehicles (EV) or Hydrogen Fuel Cell Vehicles (HFCV). Retrofit system manufacturers must submit applications including descriptions of the retrofit system, original parent vehicle, modifications, compliance verification, application range, installed samples, authorized installers, and conversion plates. Type approval requires meeting general requirements for design, construction, durability, and failure communication, plus specific requirements in Annexes 5A for EVs and 5B for HFCVs. Only authorized installers may perform conversions, and manufacturers must provide installation documents and end-user manuals.

The eighth meeting of the Informal Working Group on EV/HFCV Retrofit Systems is scheduled for Tuesday 21st April 2026. The agenda includes coordination and organization of work with reference to GRPE-92-14, EVHFCV-02-02, GRPE-93-22-Rev.1, GRSP-78-17, GRVA-24-07, and GRPE-94-06, electrical safety review, cybersecurity, braking, EMC, and UN draft documentation review. Future meetings are planned for 11th June, 2nd July, and 9th September, with hybrid and online formats.

The Informal Working Group on EV/HFCV Retrofit Systems held its seventh meeting on 5th March 2026. The group adopted the provisional agenda, approved minutes of the previous meeting, and acknowledged ongoing activities under GRPE, GRSP and GRVA. Electrical safety review will continue once clarification regarding UN R100 is available. Cybersecurity discussions covered very old vehicles, older vehicles without cybersecurity provisions, and modern vehicles compliant with UN R155. Braking aspects and the structure of the draft UN Regulation were discussed, including vehicle versus system approval approaches and minimum and maximum vehicle age within the regulation’s scope.

The Informal Working Group on EV/HFCV Retrofit Systems held its eighth meeting on 21 April 2026. The group discussed cybersecurity principles, requiring retrofitted vehicles not to reduce safety or cybersecurity performance compared with UN R155 requirements, with differentiated approaches for base vehicles approved or not approved to UN R155. Braking compliance, EMC testing references, and UN draft regulation changes including renaming to “vehicles intended to be transformed into pure electric vehicles” and introducing Electric Powertrain Retrofit Systems definitions were addressed. PTI-related aspects and the need for written contributions were highlighted before providing the draft regulation to GRPE in October.

The agenda includes coordination of work referencing GRPE-92-14, GRPE-93-22/Rev.1, GRSP-78-17, and GRPE-94-06, electrical safety review, cyber security, braking, EMC, power determination and battery range, and draft text for the proposed UN Regulation. Additional meetings are scheduled for 2nd July (Hybrid, Brussels) and 9th September (Online).