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UN R39 Supplement 1 (02 series) · UNECE Regulation No. 39 (ECE R39) — Uniform provisions concerning the approval of vehicles with regard to the speedometer and odometer equipment including its installation.

UN R39 — Supplement 1 to the 02 series of amendments

Base text → Supplement 1

Adopted at the WP.29 198th sessionEntry into force 2026-09-30
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What changed
  • Legibility by day and night is not required for a speedometer in a Field of Vision Assistant (FVA) compliant with Regulation No. 125 or 176.
  • If more than one speedometer or odometer is fitted, all of them must comply with all the requirements of this Regulation when displayed.
Why
  • The speed that an FVA displays is not the primary source of information.
  • The visibility requirements for the FVA allow mandatory information, such as the vehicle speed, on the FVA only as a secondary source.

Q1What changed2 changes

Day and night legibility of a speedometer in an FVA (para. 5.2.)

The display of the speedometer must be clearly legible both day and night. This provision now does not apply to a speedometer in the Field of Vision Assistant (FVA) compliant with UN Regulation No. 125 or 176. Before this supplement, the paragraph had no such exemption. The requirements on the location of the display and on the range of speeds do not change.

The display of the speedometer shall be located within the direct field of view of the driver and must be clearly legible both day and night. The provision on legibility during day and night does not apply to a speedometer in the Field of Vision Assistant (FVA) compliant with the technical requirements of UN Regulation No. 125 or UN Regulation No. 176. The range of speeds displayed must be sufficiently wide to include the maximum speed of this type of vehicle as stated by the manufacturer.

More than one speedometer or odometer (para. 5.1.)

If more than one onboard speedometer or odometer is fitted, all of them must comply with all the requirements of this Regulation when displayed. The words “when displayed” are new. The paragraph also adds a comma after “Tachograph Replacement Units”.

An onboard speedometer and odometer complying with the requirements of this Regulation shall be fitted to the vehicle to be approved. If more than one onboard speedometer or odometer is fitted to the vehicle, all these speedometers and odometers shall comply with all the requirements of this Regulation when displayed. Additional graduations and numerical values are not permitted. Tachographs or Recording equipment, or Tachograph Replacement Units , are not considered to be an on-board speedometer or odometer for the purpose of this paragraph.
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Q2Why it changed

Proposed by
Expert from the International Organization of Motor Vehicle Manufacturers (OICA)
Working party
GRSG, 130th session (October 2025)

Reasons

  • The aim is to clarify that the night and day visibility requirement does not apply to an FVA approved to Regulation No. 125 or 176. The speed that the FVA displays is not the primary source of information.

    Sources (2)
    “to clarify that Field of Vision Assistant (FVA) approved to UN Regulations No. 125 or 176 are not to be considered with regard to the visibility requirement during night and day”
    “since the speed displayed by FVA is not the primary source of information”

  • The visibility requirements for the FVA allow mandatory information, such as the vehicle speed, on the FVA only as a secondary source. This is because mandatory information must be permanently visible under all foreseeable circumstances.

    Sources (2)
    “mandatory information (such as the vehicle speed) may only be displayed via FVA as a secondary source of that information”
    “This restriction is done because mandatory information shall be permanently visible under all foreseeable circumstances.”

  • The proposal says that UN Regulation No. 39 contradicts the FVA Regulation, because the FVA Regulation permits speed display switch off and reduced display. The FVA Regulation names the speedometer as an example of information allowed in Field of Vision Assistant Area 2.

    Sources (2)
    “There is a contradiction between UN Regulation No. 39 and the FVA Regulation No. [176], in that the latter permits speed display switch off and reduced display.”
    “specifically mentions the speedometer is one of the examples of information allowed in the Field of Vision Assistant Area 2.”

Document trail

  1. 2025-07ProposalECE/TRANS/WP.29/GRSG/2025/13Proposal by the expert from OICA
  2. —RevisedGRSG-130-25-Rev.1Amendment to the proposal by the expert from the Kingdom of the Netherlands
  3. —Working party adoptsECE/TRANS/WP.29/GRSG/109Session report, para. 46
  4. 2026-01Sent to WP.29ECE/TRANS/WP.29/2026/21Text that GRSG sent to WP.29 and AC.1
  5. 2026-03WP.29 adoptsECE/TRANS/WP.29/1190Adopted at the 198th session (session report, para. 114)
  6. 2026-09-30In forceC.N.404.2026.TREATIES-XI.B.16.39UN depositary notification

Q3Who is affected

Vehicle manufacturer

  • Apply the day-night legibility exemption only to a speedometer in an FVA compliant with Regulation No. 125 or 176.
  • With more than one speedometer or odometer, make sure each complies with all requirements of this Regulation when displayed.

Component supplier

  • If your FVA shows the vehicle speed, give the manufacturer evidence that it complies with Regulation No. 125 or 176.

Technical service / Approval authority

  • Check that the FVA complies with Regulation No. 125 or 176 before you skip day-night legibility checks on its speedometer.
  • With more than one speedometer or odometer, check each against all requirements of this Regulation when displayed.

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ⓘ This report gives advice only. It is not legal or type-approval advice.

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