Proposal to amend UN R171 to modify paragraphs 5.5.4.2.8.2., 5.3.7.2.4.2., 5.3.7.2.6.1., 6.4.2., 7.2.3.1., 14.2., and Annexes 3 and 4. The amendments include clarifications regarding driver engagement determination, system boundary conditions, automatic acceleration in non-highway environments, system-initiated manoeuvres tracking, production discontinuation, documentation retention periods, supplier safety management arrangements, and test scenario specifications for bicycle and cyclist targets.

Consolidated proposal to clarify provisions in the original version of the Regulation. See GRVA/2026/16 for the proposed amendments.

Proposal to amend UN R171 based on GRVA/2026/15:

• Insert new introduction paragraph 17 establishing the regulation on current technology with continuous review based on data
• Amend paragraphs on system boundaries, driver disengagement detection, manoeuvre initiation, and Risk Mitigation Function
• Clarify driver state monitoring and visual engagement assessment
• Update terminology for powertrain
• Delete duplicate definitions
• Add processes for safety management during operation phase
• Insert definition of “Evidence”
• Clarify base and extended test requirements
• Update language from “cyclist” to “bicycle” in test scenarios

Proposal to clarify UN R171 on Driver Control Assistance Systems (DCAS):

• Clarifications to definitions, adding “Highway-like road” definition
• Clarifications to system boundary detection, manoeuvre initiation, and driver disengagement requirements
• Amendments permitting withholding of hands-on requests on highway-like roads up to 130 km/h
• Clarifications on Risk Mitigation Function terminology
• Amendments allowing alternative strategies for lower-speed lane changes
• Addition of operational phase safety management processes
• Clarifications on testing requirements and non-rule-based algorithm repeatability.

Consolidated version based on WP.29/2025/7 as amended by WP.29-195-05, WP.29/2025/144, GRVA-24-18, and GRVA-24-19. See GRVA/2026/18 for the proposed amendments.

Since the 24th (January 2026) GRVA session, the ADAS task force held an online session on 3 March 2026. A 02 series of amendments to UN R171 (GRVA-24-17/Rev.2) was approved and submitted to WP.29 as WP.29/2026/86. Draft supplements and consolidated and extracted versions for 00 and 01 series were prepared (GRVA-24-18-A, GRVA-24-19-A, GRVA-24-18-B, GRVA-24-19-B). For the 25th GRVA session, editorial modifications and consolidated and extracted versions were submitted (GRVA/2026/14, GRVA/2026/15, GRVA/2026/16, GRVA/2026/17, GRVA/2026/18). The task force seeks guidance on provisions for DCAS use on highway-like roads and feedback on existing provisions following practical implementation of UN R171. The ADAS task force will be maintained with a break in activities pending stakeholder inputs and concrete proposals.

Proposal to amend the original version (GRVA/2026/15), insert para. 5.3.7.2.1.13. to require the manufacturer to describe in the safety concept the system behaviour in case the driver is detected to be disengaged during a manoeuvre; amend the original version and the 01 series (GRVA/2026/15 and GRVA/2026/17), amend para. 3.5.1. of Annex 3 to require the manufacturer to demonstrate to the Type Approval Authority at least every three years that the safety management system continues to comply with requirements; amend the 01 and 02 series (GRVA/2026/17 and WP.29/2026/86), amend para. 2.3.2. of Appendix 2 of Annex 3; amend the 02 series (WP.29/2026/86), amend para. 4.2.5.2.19.2.1. of Annex 4; and amend the original version, 01 series and 02 series (GRVA/2026/15, GRVA/2026/17 and WP.29/2026/86), amend para. 4.2.5.2.14.1.2. of Annex 4 and para. 4.2.5.2.14.2.1. of Annex 4.

Proposal to amend GRVA/2026/16, based on GRVA-25-46. Insert new Introduction paragraph 17 regarding DCAS technology development and continuous review; amend paragraph 2.11. to define Target Lane; amend paragraph 5.3.5.1. to specify system boundary detection and feature transition requirements; amend paragraph 5.3.7.1.4. regarding steering support at boundary conditions; amend paragraph 5.3.7.2.1.1. to clarify driver disengagement detection timing; insert new paragraph 5.3.7.2.1.13. regarding manufacturer description of system behaviour during driver disengagement; amend paragraph 5.3.7.2.3.1. regarding driver confirmation time; amend paragraph 5.3.7.3.1. concerning risk mitigation function compliance; amend paragraph 5.3.7.5.1.1.2. regarding headway configuration notification; insert footnote 3 defining initiation of powertrain; amend paragraph 5.5.3.1. to clarify system off mode default status; amend paragraph 5.5.4.1.1. removing reference to system-initiated manoeuvres; amend paragraph 5.5.4.2.2.3. regarding warning escalation strategy; amend paragraphs 5.5.4.2.5.2. and 5.5.4.2.5.2.1. regarding visual disengagement assessment; amend paragraphs 5.5.4.2.7. and 5.5.4.2.7.1. regarding disengagement detection strategies; amend paragraph 5.5.4.2.8.1. regarding system activation disabling; amend paragraph 6.2.4.1. regarding approaching vehicle deceleration at speeds up to 60 km/h; amend paragraph 14.2. regarding production discontinuation; delete Annex 3 paragraphs 2.15. and 2.16. defining Highway and Non-Highway roads; amend Annex 3 paragraph 3.1.1. regarding documentation package retention; renumber Annex 3 paragraph 3.5.7. to 3.4.5. and insert new paragraph 3.4.5. regarding system information strategy; insert new paragraph 3.5.5. regarding safety management processes during operation phase; renumber former paragraphs 3.5.5. and 3.5.6. to 3.5.6. and 3.5.7. respectively; insert Annex 3 Appendix 2 with new definitions section; amend Annex 4 Introduction regarding test requirements and extended tests; amend paragraph 4.2.2.1. regarding longitudinal control distance; insert new paragraph 4.2.2.2. regarding non-repeatable outcomes; amend paragraphs 4.2.5.2.8.1.2., 4.2.5.2.10.1.1., and 4.2.5.2.12.1.1. regarding bicycle target specifications; delete paragraph 4.2.5.2.14.1.2.; amend paragraph 4.2.5.2.14.2.1. regarding test execution requirements; and amend Annex 5 paragraphs 3.4.8.2. and 3.5.5.1. regarding M&S data and simulation tool criticality assessment.

Proposal to:

• Amend Introduction para. 17 to clarify DCAS development based on current technology and data
• Amend para. 2.11 to delete “the” before “travel”
• Insert new para. 2.28.1. defining “Highway-like road” with characteristics including at least two lanes, designated speed limit of at least 80 km/h, physical separation dividing opposite traffic, and absence of at-grade pedestrian crossings, rail crossings, or road intersections
• Amend para. 5.3.5.1 to specify system shall leave active mode with exception of driver unavailability response
• Amend para. 5.3.7.1.4 to delete “the” before “front tyre”
• Amend para. 5.3.7.2.1.1 to change “detected” to “deemed” and specify disengagement duration of more than 2s
• Insert new para. 5.3.7.2.1.13 requiring manufacturer to describe system behaviour if driver detected disengaged during manoeuvre
• Amend para. 5.3.7.2.3.1 to delete requirements reference and require sufficient time for driver confirmation
• Amend para. 5.3.7.2.5.3.1 to add “or highway-like road” to highway operation requirements
• Delete para. 5.3.7.2.4.3 and renumber paras. 5.3.7.2.4.4 to 5.3.7.2.4.11 as 5.3.7.2.4.3 to 5.3.7.2.4.10
• Amend para. 5.3.7.3.1 to reference systems driver unavailability response and RMF requirements of 04 series UN R79
• Amend para. 5.3.7.3.3 to specify system capable of lane changes during driver unavailability response in compliance with RMF requirements
• Amend para. 5.5.4.2.2.3 to renumber and require warning strategies prioritize simultaneously activated emergency assistance systems
• Amend paras. 5.5.4.2.5.2 and 5.5.4.2.5.2.1 to specify visual disengagement criteria, dashboard consideration limited to 3 seconds, and visual re-engagement duration of at least 200 milliseconds
• Amend para. 5.5.4.2.6.5 to allow HOR withholding on highway-like roads at speeds up to 130 km/h and require verification of road characteristics for at least 500 m or 30 seconds, demonstration of safe cyclist operation, and HOR at least 7s before end of highway-like road
• Amend paras. 5.5.4.2.7 and 5.5.4.2.7.1 to add assessment of gaze direction changes and insert new para. 5.5.4.2.7.1
• Amend para. 6.2.4.1 to permit deviation from assessment at speeds up to 60 km/h with manufacturer explanation to Type Approval Authority
• Amend para. 14.2 to change “definitely” to “definitively”
• Amend Annex 1 to add para. 6.4.1 for system capability of withholding HORs on highway-like roads
• Delete Annex 3 paras. 2.15 and 2.16 defining “Highway” and “Non-Highway”
• Amend Annex 3 para. 3.1.1 to change “definitely” to “definitively”
• Renumber Annex 3 para. 3.5.7 to 3.4.5 and amend to require system information strategy

This document consolidates amendments to WP.29/2026/86 by GRVA/2026/14, GRVA-25-46, and GRVA-25-51. It proposes to amend para. 5.5.4.2.8.2., renumber reference to para. 5.3.7.2.1.1.1. to 5.3.7.2.4.10., amend paras. 5.3.7.2.4.2., 5.3.7.2.5.3.1., 5.3.7.2.6.1., 6.4.2., and 7.2.3.1., replace “definitely” with “definitively” in para. 14.2. and Annex 3 paras. 3.1.1.a and 3.1.1.b, insert new para. 16.2.3. effective 1 September 2029, amend Annex 1 para. 6.4., renumber reference in Annex 3 para. 3.5.7., amend Annex 3 Appendix 2 para. 2.3.2., amend text in Annex 4 diagrams at paras. 4.2.5.2.8.1.2., 4.2.5.2.10.1.1., 4.2.5.2.12.1.1., 4.2.5.2.16.1.3., and 4.2.5.2.20.1.3., delete second diagram in para. 4.2.5.2.14.1.2., amend paras. 4.2.5.2.14.2.1. and 4.2.5.2.19.2.1., and delete words in para. 4.2.5.2.19.1.1.