WP.29/2026/215
UN R171: Proposal for a Supplement 4
Source(s)
Date
7 Sep 2026
Status
Formal WP.29 review
Subject
Impact
Original text | Supplement 4
Meeting(s)

Proposal to:

  • Insert new Introduction paragraph 17 describing continuous review of DCAS based on technology development and monitoring data,
  • Amend para. 2.11. to define ‘Target Lane’,
  • Amend para. 5.3.5.1. to specify system boundary detection and assistance termination,
  • Amend para. 5.3.7.1.4. to require warning signals when steering support diminishes,
  • Amend para. 5.3.7.2.1.1. to require driver non-disengagement for 2 seconds before manoeuvre initiation,
  • Insert para. 5.3.7.2.1.13. requiring manufacturer description of system behaviour if driver disengages during manoeuvre,
  • Amend para. 5.3.7.2.3.1. to ensure sufficient driver confirmation time,
  • Amend para. 5.3.7.3.1. to require compliance with 04 or later series of UN R79 Risk Mitigation Function,
  • Amend para. 5.3.7.5.1.1.2. to require driver information on headway configuration below 2 seconds,
  • Amend para. 5.5.3.1. to require ‘off’ mode at powertrain initiation,
  • Amend para. 5.5.4.1.1. to add intended driver-confirmed manoeuvres to driver information,
  • Renumber and amend para. 5.5.4.2.2.3. to prioritize simultaneous emergency assistance system warnings,
  • Amend paras. 5.5.4.2.5.2. and 5.5.4.2.5.2.1. to define visual disengagement and re-engagement criteria,
  • Amend para. 5.5.4.2.7. to add disengagement detection strategies,
  • Amend para. 5.5.4.2.8.1. to disable system activation upon prolonged insufficient engagement,
  • Amend para. 6.2.4.1. to specify deceleration limits for approaching vehicles,
  • Amend para. 14.2. to exclude software update approvals from discontinuation determination,
  • Delete Annex 3 paras. 2.15. and 2.16.,
  • Amend para. 3.1.1. to specify documentation package retention periods of 10 years from production discontinuation,
  • Renumber para. 3.5.7. to 3.4.5.,
  • Insert new para. 3.5.5. on safety management during operation phase,
  • Renumber former para. 3

UNECE server
Excerpts from session reports
GRVA | Session 25 | 18-22 May

41. During the consultations, the expert from CLEPA presented the status report of the Task Force on Advanced Driver Assistance Systems (GRVA-25-05), providing an overview of the documents submitted for review and their descriptions, the guidance sought from GRVA on the introduction of the “highway-like road” concept in the 01 series of amendments, and considerations for the next phase of DCAS. The expert from China stated that this concept was incompatible with China’s road classification system. The expert from France noted that the concept was intended for the 02 series of amendments only. The expert from Norway inquired about the potential safety benefits of introducing this concept. The experts reviewed the official documents tabled under this agenda item and considered amendment proposals submitted by the expert from the United Kingdom. They subsequently drafted informal documents GRVA-25-56, GRVA-25-57 and GRVA-25-58.

42. During the official part of this session, GRVA:

  1. Endorsed a status report (GRVA-25-05) of the Task Force on Advanced Driver Assistance Systems.
  2. Noted ECE/TRANS/WP.29/GRVA/2026/15 and ECE/TRANS/WP.29/GRVA/2026/17.
  3. Requested the secretariat to distribute informal GRVA-25-46 (part 3 only) with an official symbol in September 2026.

43. GRVA adopted the following documents and requested the secretariat to submit them to WP.29 and AC.1 for consideration and vote in November 2026:

  1. ECE/TRANS/WP.29/GRVA/2026/16 (amended by GRVA-25-56),
  2. ECE/TRANS/WP.29/GRVA/2026/18 (amended by GRVA-25-57).

44. GRVA adopted ECE/TRANS/WP.29/GRVA/2026/14 (amended by GRVA-25-58) and requested the secretariat to submit it to WP.29 and AC.1 for consideration and vote in June 2026.