The methodologies for determining the correlation parameters necessary for reflecting the change in the regulatory procedure are set out in Commission Implementing Regulation (EU) 2017/11532 and, with regard to light commercial vehicles, in Commission Implementing Regulation (EU) 2017/11523. To facilitate the transition to the new regulatory test procedure for measuring CO₂ emissions and fuel consumption from light duty vehicles (the Worldwide Harmonised Light Vehicles Test Procedure, the WLTP), the correlation procedure for passenger cars should be aligned with that for light commercial vehicles to the extent possible.

The designation of contact points at type approval authorities and technical services by Member States should be clarified so that the electronic signing keys needed for the formal correlation tool runs can be provided in an efficient and secure way.

In the case of M1 vehicles with a technically permissible maximum laden mass of 3 000 kg or more, it is appropriate to provide manufacturers with the same possibility as for N1 vehicles to either derive NEDC road load coefficients from the WLTP tests or use the tabulated values set out in Table 3 of Annex 4a to Regulation No 83 of the Economic Commission for Europe of the United Nations (UNECE) (UN/ECE Regulation No 83)4. This should facilitate the type approval testing of this specific group of vehicles.

Based on the further development of the correlation tool, certain input data parameters are no longer needed while other data of an administrative nature should be added to ensure a traceable and verifiable process.

It is also appropriate to introduce the use of electronic hash codes for the correlation output files. Certain limited and non-confidential output of the correlation tool should be made available to the Commission to ensure the continuous development and improvement of the correlation tool and provide the means for further verification of the correlation results.

The calculation of the NEDC CO₂ reference value should be simplified by removing the need for post-processing of the WLTP test results and the calculation of the delta between the correlation tool simulated WLTP CO₂ value and the NEDC CO₂ value. The new calculation method provides an absolute NEDC CO₂ reference value and any deviation of the correlation tool should be easily calculated and shown in the non-confidential summary output file. This approach reduces significantly the risk for errors in the calculation of the reference values.

It is moreover appropriate to simplify the calculation of the combined and phase-specific fuel consumption values. The fuel consumption should be calculated from the final NEDC CO₂ value (declared, correlation tool, or physical test values) using the formulae specified in Annex XII to Commission Regulation (EC) No 692/20085.

Annexes I and II to Implementing Regulation (EU) 2017/1153 should therefore be amended accordingly.

The measures provided for in this Regulation are in accordance with the opinion of the Climate Change Committee,