The agenda for the 74th session of the Informal Working Group on Wet Grip of Worn Tyres scheduled for May 19th, 2026, remotely via Teams. The agenda includes welcome and opening remarks, adoption of the agenda and minutes of the previous 73rd session meeting held 31 March 2026, discussion of the workplan 2025 for C1 tyres status test campaign, and determination of the next meeting date.
LED replacement light sources without type approval are being sold online and offline and are unsafe for public roads; vehicles equipped with such products would fail PTI. LED replacement light sources with type approval are available either at national level or according to UN R37, and are safe and legal for public roads; vehicles equipped with approved LED replacement light sources shall NOT fail PTI. Approval marking on installed light sources is not accessible during PTI; verification may involve a sticker on headlamp housing, type approval documents, or packaging, with removal of the light source as a last resort to verify the approval marking.
Single N1 and N2 vehicles with fluted brake drums for parking brakes cannot be inspected on roller and plate test benches or in test drives. Electric parking brake systems cannot be tested on roller and plate test benches or test drives, and wheels cannot be turned on lifts to inspect for damages or bearing wear. Some vehicles have hydraulic braking systems with brake fluid reservoirs not accessible without dismantling or special tools, requiring removal of covers, fasteners, and screws to access brake fluid for inspection. PTI inspection provisions require updating to address these vehicle design variations.
The IWG on PTI Provisions for PTI works on whole-life compliance, testing ADAS/ADS at Periodic Technical Inspection, ePTI provisions, driverless vehicle inspection, and anti-tampering measures across 2025–2027. Provisions for PTI exist in at least 20 UN Regulations as of 8 April 2026, though PTI experts deem some insufficient and additional provisions may be needed. The proposed update procedure requires the IWG to generate a current provisions list, present needs to WP.29, develop proposals for the first 2–3 UN Regulations, defend each proposal in relevant GRs, and transmit outcomes to WP.29 for decision.
The meeting will address coordination of work, pollution emission control in PTI including PN measurement, NOx measurement, and Euro 7, Advanced Driver Assistance Systems and Automated Driving Systems including PTI using diagnostic devices and inspections of automated vehicles, PTI provisions for brakes, lighting devices coordination and inspection, and 1997 Agreement updates.
Proposal to enable application of the designation “twinned wheels” across all Category L vehicles.