Proposal for a new UN Regulation establishing uniform provisions for type approval of Electric Powertrain Retrofit Systems (EPRS) designed for conversion of vehicles of categories M and N to full electric propulsion. The regulation does not apply to vehicles holding approval under UN R155 or UN R156. It sets out requirements for EPRS manufacturers, installers, markings, approval procedures, general and specific technical requirements for retrofit systems, installer authorization and training, documentation to be provided by manufacturers, conformity of production, modification and extension of approvals, and penalties for non-conformity.

Provisional agenda for the twelfth meeting of the IWG on EV/HFCV-RS to be held on 28 September 2026. The agenda covers adoption of the agenda, approval of minutes from the previous meeting, coordination and organization of work, power determination and battery range, UN draft documents, and any other business, with the next meeting scheduled for 8 October 2026.

Minutes of the eleventh meeting of the IWG on EV/HFCV Retrofit Systems held on 9 September 2026. The group adopted the provisional agenda and reviewed the draft UN Regulation on EV/HFCV retrofit systems. Key discussions addressed the regulatory concept for approval of the Electric Powertrain Retrofit System combined with installation requirements and vehicle testing, vehicle scope including possible exclusion of older vehicles and those subject to UN Regulations Nos. 155 and 156, and confirmation that HFCV provisions would remain as placeholders for later development. The updated working document will be circulated before submission to GRPE in October 2026.

This regulation proposes uniform provisions for the approval of electric powertrain retrofit systems (EPRS) intended for the conversion of vehicles of categories M and N to electric propulsion. It establishes requirements for EPRS design, installation by authorized installers, type approval procedures, application ranges, markings, conformity of production, and modification or extension of approvals. Specific requirements for compliance with applicable UN Regulations are defined, including electromagnetic compatibility, braking, power measurement, rechargeable energy storage systems, and mass and dimension limits. The regulation applies to both pure electric vehicles (EV) and hydrogen fuel cell vehicles (HFCV).

The agenda includes adoption of the coordination and organization of work with reference to GRPE-92-14, EV/HFCV-02-02, GRPE-93-22-Rev.1, GRSP-78-17, GRVA-25-19, WP.29-199-16, and other documents, electrical safety review, braking, EMC, power determination and battery range, UN draft discussion, and any other business, with a next meeting scheduled for 8th October online.

The Informal Working Group on EV/HFCV Retrofit Systems held its tenth meeting on 2nd July 2026 in Brussels. The group reviewed progress reports presented to WP.29 Working Parties, referencing GRPE-92-14, GRPE-93-22-Rev.1, GRSP-78-17, GRVA-24-07, GRPE-94-06, and GRVA-25-19. Electrical safety will be reviewed later pending clarification on UN Regulation No. 100. The group excluded UN Regulation No. 155 from draft requirements to avoid cybersecurity complications. Braking requirements for retrofitted vehicles and applicability of UN Regulation No. 13/13-H require further assessment. Further coordination with the EMC Informal Working Group is required. The group distinguished battery range requirements for light-duty vehicles from heavy-duty vehicles.

Updates and comments on the draft uniform provisions establishing harmonized methods for the approval of vehicles transformed with electric powertrain retrofit systems for categories M₁–M₃ and N₁–N₃. Requirements cover application for approval, markings on transformation plates, type approval procedures, general and specific requirements for retrofit systems, application range definitions, installer authorization and responsibilities, information to be provided by manufacturers to installers, end-user manuals, conformity of production procedures, modification and extension of approval, withdrawal of approvals, and notification procedures to contracting parties. Specific compliance is required with UN R10, UN R13, UN R13H, UN R85, UN R100, UN R121, UN R134, UN R138, UN R79, UN R155, UN R154, and UN R49, with staged implementation dates for certain requirements such as rechargeable energy storage system compliance from 1 September 2027 onwards and braking system compliance from 1 September 2026 onwards.

Proposal to establish uniform provisions for approval of electric powertrain retrofit system installation on vehicles of categories M₁–M₃ and N₁–N₃:

• Add abbreviations section,
• Insert definitions of electric powertrain retrofit system, vehicle installation approval, approval of electric powertrain retrofit system, type of electric powertrain retrofit system, original vehicle, parent vehicle, and member of family,
• Modify scope to apply to electric powertrain retrofit systems and their installation on vehicles transformed,
• Delete prior scope provisions,
• Renumber paragraphs accordingly,
• Insert markings requirements for retrofit system installation plates,
• Add approval procedures and communication forms,
• Insert specific requirements regarding electric powertrain retrofit systems with compliance to applicable UN Regulations including UN R10, UN R13, UN R13H, UN R85, and UN R100,
• Insert application range provisions,
• Modify installer authorization requirements,
• Insert information requirements for retrofit system manufacturers to provide installers,
• Insert end-user manual requirements,
• Add provisions for periodic technical inspection including retrofit system identifiability and certification requirements,
• Insert conformity of production procedures,
• Modify procedures for extension and modification of approval,
• Modify penalties for non-conformity and withdrawal procedures,
• Insert introductory provisions explaining the Regulation’s purpose,
• Insert names and addresses reporting requirements for technical services and type approval authorities,
• Split Annexes 1, 2, 3, 4, 5, 6, and 7 into separate provisions for electric vehicles and hydrogen fuel cell vehicles,
• Insert Annex 5 specific requirements aligned with UNECE Regulations including electromagnetic compatibility, braking, electric drive train power measurement, rechargeable energy storage system compliance with phased timeline from date of entry into force to 1 September 2031 for UNECE Regulation 100 compliance, and other applicable regulations.

Proposal to add an Abbreviations section, redefine scope to apply to electric powertrain retrofit systems for M₁–M₃ and N₁–N₃ vehicle categories intended to be transformed into pure electric vehicles (EV) or Hydrogen Fuel Cell Vehicles (HFCV), replace “conversion” terminology with “transformation” throughout, separate requirements into distinct annexes for EVs and HFCVs, add a Provisions for PTI section specifying retrofit system identifiability and certificate requirements, insert transitional dates for REESS compliance with UN Regulation 100 (31 August 2027 onwards for new types; 31 August 2029 onwards for all types), insert transitional dates for braking compliance with UN Regulation 13 (31 August 2026–2029 for new types; 31 August 2028–2031 for all types) and UN Regulation 13-H (31 August 2028 for new types; 31 August 2030 for all types), add mass distribution verification requirements when unladen weight variation exceeds 5%, and align mass and dimensions procedures with regional requirements such as EU 2021/535.

The provisional agenda for the tenth meeting of the Informal Working Group on EV/HFCV Retrofit Systems on Thursday 2nd July 2026 includes adoption of the agenda, approval of minutes, coordination and organization of work with reference to GRPE-92-14, EV/HFCV-02-02, GRPE-93-22/Rev.1, GRSP-78-17, GRVA-25-19, and WP.29-199-16, electrical safety review, braking, EMC, power determination and battery range, UN Draft, and any other business, with subsequent meetings scheduled for 9th September online and 8th October online.

The Classic Car Retrofit Consortium represents SMEs performing small-series and classic car retrofits, averaging around 10 vehicles per year. The current draft regulation applies OEM-level type-approval logic designed for large-series fleet retrofits, which would eliminate the existing SME sector without materially improving safety. Specific challenges include destructive REESS testing costs of approximately 100,000 EUR per battery pack type, full-vehicle EMC testing costs around 30,000 EUR per car, and cybersecurity requirements unsuitable for classic vehicles. CCRC proposes either clarifying the regulation’s scope to exclude classic car retrofits, or developing a tailored regulatory framework specifically for classic cars produced in small numbers.

This consolidated draft text proposes uniform provisions for approving vehicles transformed into electric vehicles (EV) or hydrogen fuel cell vehicles (HFCV) with electric powertrain retrofit systems. The regulation defines retrofit systems as all devices and components necessary to operate vehicles in electric mode, including powertrains, energy storage systems, management systems, and vehicle inlets. It specifies application procedures, marking and approval requirements, technical specifications for retrofit systems, installer qualifications and authorization, conformity of production procedures, modification and extension of approvals, and penalties for non-compliance. The regulation applies to vehicles of categories M and N and requires compliance with relevant UN Regulations including those addressing electromagnetic compatibility, braking, power measurement, and electric powertrains. Specific technical requirements address surveillance systems, anti-tampering provisions, performance parameters, dimensional and mass tolerances, and acoustic devices.

The Informal Working Group on EV/HFCV Retrofit Systems held its ninth meeting on 11th June 2026. The group discussed electrical safety, cybersecurity, braking, EMC, power determination, battery range, and the overall approval concept for retrofit systems. Discussions covered UN Regulations 100, 155, 13/13-H, 10, 85, 177, 154, and 138. The group agreed to approve retrofit systems together with compatible vehicle families and to exclude hydrogen fuel cell provisions pending further technical input. RME agreed to coordinate benchmarking exercises on power thresholds and range/durability requirements. Future meetings were scheduled for 2 July 2026, 9 September 2026, and 8–9 October 2026.

The EV/HFCV Retrofit Systems IWG has held nine meetings since creation and focused on EV retrofit requirements. The group compiled requirements for Electrical Safety (UN R100), Braking (UN R13/R13H), Cybersecurity (UN R155), and EMC (UN R10) with participation from respective GRs experts. Next activities include continuation of discussions on electrical safety, braking, cybersecurity, and EMC; net power and electric consumption determination; Family/Parent definition; and PTI provisions. A regulation draft for EV retrofit will be delivered as an informal document to the next GRPE session in October, with adoption expected in the first half of 2027.

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).

OICA-CLEPA-EME comments on German proposal GRVA-25-07 to require the approval authority granting UN R155 or UN R156 type approvals to use CSMS or SUMS certificates signed by the same approval authority. OICA-CLEPA-EME identify that CSMS and SUMS are Management Systems covering entire manufacturer organizations, and mandating the same approval authority for Management Systems certificates and approvals will have significant consequences for original equipment manufacturers typically using multiple approval authorities in homologation. The submission proposes keeping text unchanged to allow different approval authorities for Management Systems certificates and type approval based on voluntary acceptance, implementing wording on information exchange if different approval authorities are involved, and establishing a horizontal approach for Management Systems with mutual recognition aspects considered.

The EV/HFCV Retrofit Systems IWG held three meetings since the last GRVA session and has compiled requirements for Electrical Safety (UN R100), Braking (UN R13/R13H), Cybersecurity (UN R155), and EMC (UN R10) with participation of respective GRs experts. Regulation drafting has started. Next activities include continuation of discussion on requirements, addressing net power and electric consumption determination, family and parent definition, and provisions for PTI, with regulation draft for EV retrofit to be delivered as informal document to the next GRPE session in October.

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 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 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.

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.

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.

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.