Text prepared by the experts of TF TPMSTI in order to align with the provisions of European Union Regulation 2019/2144 and to introduce the TPMS requirements for all vehicle categories, including trailers. The proposal addresses the communication interface protocol of TPMS between towing and towed vehicles of categories N2, N3 and O3, O4, respectively (described in Annex 5 on the basis of the ISO bus requirements) in alignment with UN R13 and ISO updates. The proposal further corrects and clarifies provisions across TPMS, TPRS and CTIS.