The document addresses accuracy calculation procedures in UN R154.04 Appendix 5, paragraph 4.2, which compares type-approval values from the mains with values at the vehicle interface for energy-related parameters of plug-in electric vehicles and other vehicles. It notes that losses of electric vehicle supply equipment and measurement uncertainties of external devices used to measure voltage and current are not considered in the accuracy calculation. OICA is developing a proposal to address both topics for submission to the 96th GRPE session.