A Study on Legal and Institutional Improvement for Strengthening Driver Warning Systems in cases of Unintended Disengagement of Level 2 Automated Driving Systems

Byoung Joon Moon; Sung Jae Ha

doi:10.22680/kasa2026.18.3.104

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2026 Vol.18, Issue 3 Preview Page Next Page

A Study on Legal and Institutional Improvement for Strengthening Driver Warning Systems in cases of Unintended Disengagement of Level 2 Automated Driving Systems 운전자가 의도하지 않은 레벨2 자율주행시스템 해제 시 운전자 경고 강화에 대한 법제도 개선방안 연구

30 September 2026. pp. 104-114

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Abstract

This study examines the safety risks associated with unintended disengagement of Level 2 automated driving systems (ADS) and proposes legal and institutional measures to strengthen driver warning requirements. Unlike Level 3 or higher automated driving systems, Level 2 systems, which simultaneously control steering and longitudinal motion, do not include a legally defined transition-demand procedure. When Level 2 systems are unexpectedly disengaged due to sensor or lane-recognition failure, adverse weather, or system malfunction, drivers may fail to recognize the need to resume manual control. Domestic and international regulatory frameworks—including the Korean Motor Vehicle Safety Standards, UN Regulation No. 157 (ALKS), UN Regulation No. 171 (DCAS), the EU General Safety Regulation, and recent U.S. regulatory trends—were comparatively analyzed, together with prior studies on driver take-over performance and real-vehicle tests of warning behavior during Level 2 disengagement. The analysis confirmed that specific warning standards for Level 2 disengagement remain insufficient both domestically and internationally; most tested vehicles provided only an indicator-light cue or visual warning, whereas multimodal warnings more effectively improve driver awareness and take-over time. Based on these findings, this study proposes three measures: domestic adoption of UN Regulation No. 171, mandatory multimodal disengagement warnings with quantitative performance criteria, and mandatory driver education for drivers of Level 2 vehicles.

Keywords

Level 2 automated driving system(레벨2 자율주행시스템)

Unintended disengagement(의도하지 않은 해제)

Driver warning system(운전자 경고시스템)

Multimodal warning(다중모달 경고)

Take-over(제어권 전환)

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Information

Publisher :Korean Auto-vehicle Safety Association
Publisher(Ko) :한국자동차모빌리티안전학회
Journal Title :Journal of Auto-vehicle Safety Association
Journal Title(Ko) :자동차안전학회지
Volume : 18
No :3
Pages :104-114
Received Date : 2026-07-20
Revised Date : 2026-08-19
Accepted Date : 2026-08-20
DOI :https://doi.org/10.22680/kasa2026.18.3.104

Journal of Auto-vehicle Safety Association ISSN:2005-9396(Print) 자동차안전학회지

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