Discussion of the 00 series of UN Regulation on Child Presence Detection Systems for passenger cars, focusing on development of Door Logic Plus concept. Door Logic Plus is defined as a system that improves performance by adding sensors to base door logic, reducing false detections and detection accuracy. The document presents comparative analysis of direct sensing and indirect sensing approaches, including pure door logic with external warning, door logic plus with buckle switch, and door logic plus with occupancy sensor. Additional time needed to develop Door Logic Plus concept and prepare proposal for documentary assessment procedure; proposes different test procedures for direct and indirect sensing systems.