49 CFR § 561.9 - Documentation of an audio-visual warning for a thermal event in the REESS.

---
identifier: "/us/cfr/t49/s561.9"
source: "ecfr"
legal_status: "authoritative_unofficial"
title: "49 CFR § 561.9 - Documentation of an audio-visual warning for a thermal event in the REESS."
title_number: 49
title_name: "Transportation"
section_number: "561.9"
section_name: "Documentation of an audio-visual warning for a thermal event in the REESS."
chapter_name: "NATIONAL HIGHWAY TRAFFIC SAFETY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION"
part_number: "561"
part_name: "DOCUMENTATION FOR ELECTRIC-POWERED VEHICLES"
positive_law: false
currency: "2026-03-24"
last_updated: "2026-03-24"
format_version: "1.1.0"
generator: "[email protected]"
authority: "49 U.S.C. 322, 30111, 30115, 30117, and 30166; delegation of authority at 49 CFR 1.95."
regulatory_source: "89 FR 104350, Dec. 20, 2024, unless otherwise noted."
cfr_part: "561"
---


# 561.9 Documentation of an audio-visual warning for a thermal event in the REESS.

At NHTSA's request, each manufacturer shall submit documentation that includes the following:

(a) The make, model, model year, and production dates of the vehicles to which the submitted documentation applies.

(b) A system diagram of the thermal event warning system.

(c) A written explanation describing the basic operation of the thermal event warning system. The explanation must identify the components of the thermal event warning system, provide descriptions of their functions and capability, and provide a logic diagram and description of conditions that would lead to triggering the warning activation.

(d) Validation results from tests to confirm the activation of an audio-visual warning in the case of a thermal event in the REESS.

(e) *Overall evaluation:* A description of the final manufacturer review/audit process and results of the final review or audit which evaluated the technical content and the completeness and verity of paragraphs (a) through (d) of this section.