Interpretation ID: NCC-230927-001 FMVSS 135 - Telltale_ St. Pierre_ Canoo

June 7, 2024

Mr. Barry St. Pierre 

Sr. Homologation Engineer  

Canoo 

19951 Mariner Ave 

Torrance, CA 90503 

barry.st.pierre@canoo.com

Dear Mr. St. Pierre: 

I write in response to your September 12, 2023 email to the National Highway Traffic Safety Administration (NHTSA) asking for information on federal requirements for telltales in light vehicle brake systems. Please note that our answer below is based on our understanding of the specific information provided in your email correspondence. 

In responding to this request, NHTSA notes that the contents of this letter do not have the force and effect of law and are not meant to bind the public in any way. This letter is only intended to provide clarity regarding existing requirements under the law at the time of signature. 

Background 

NHTSA is authorized by the National Traffic and Motor Vehicle Safety Act (Safety Act, 49 U.S.C. Chapter 301) to issue Federal Motor Vehicle Safety Standards (FMVSS) setting performance requirements for new motor vehicles and new items of motor vehicle equipment. The Safety Act requires manufacturers to self-certify that their vehicles and equipment conform to all applicable FMVSS in effect on the date of manufacture. NHTSA also investigates safety-related defects. 

Your email correspondence seeks clarification of the requirement in 49 CFR § 571.135 S5.5.5(a) that visual indicators “shall have letters not less than 3.2mm (⅛ inch) high.” You state correctly that, if the telltale is the word “BRAKE,” it must meet the height requirement. You also ask about the specific proposed brake and ABS icon symbols pictured in your correspondence. In particular, you ask: (1) if a brake symbol includes the letter “P” as part of the symbol, whether it is sufficient for the symbol as a whole to meet the 3.2 mm height requirement of S5.5.5(a), or whether the letter “P” by itself must meet the height requirement; and (2) if an antilock braking system symbol includes the letters “ABS” as part of the symbol, whether it is sufficient for the symbol as a whole to meet the 3.2 mm high requirement, or whether the letters “ABS” by themselves must meet the height requirement. 

Discussion 

As you acknowledge in your correspondence, 49 CFR § 571.135 (FMVSS 135) S5.5.5(a) specifies labeling requirements for light vehicle brake systems. It states: 

Each visual indicator shall display a word or words in accordance with the requirements of Standard No. 101 (49 CFR 571.101) and this section, which shall be legible to the driver under all daytime and nighttime conditions when activated.
Unless otherwise specified, the words shall have letters not less than 3.2 mm (⅛ inch) high and the letters and background shall be of contrasting colors, one of which is red. Words or symbols in addition to those required by Standard No. 101 and this section may be provided for purposes of clarity. 

49 CFR § 571.101 (FMVSS 101), in turn, includes requirements for telltales and indicators. Section 5.2.1 states, in relevant part: 

[E]ach control, telltale and indicator that is listed in column 1 of Table 1 or Table 2 must be identified by the symbol specified for it in column 2 or the word or abbreviation specified for it in column 3 of Table 1 or Table 2. If a symbol is used, each symbol provided pursuant to this paragraph must be substantially similar in form to the symbol as it appears in Table 1 or Table 2. 

Table 1 of FMVSS 101 shows the required telltales for the items for which you request clarification: brake system malfunction and anti-lock brake system malfunction. These telltales have specific words or abbreviations that must be used as identifiers. Specifically, the word “Brake” must be used to indicate brake system malfunction. The words “Antilock” or “Anti-lock,” or the abbreviation “ABS,” must be used to indicate antilock brake system malfunction for vehicles subject to FMVSS Nos. 105 or 135. Unlike certain other items, Table 1 of FMVSS 101 does not permit the use of a symbol as an alternative to words or abbreviations to indicate either a brake system malfunction or an anti-lock brake system malfunction. Further, these required words or abbreviations must comply with the 3.2 mm height requirement of FMVSS 135 S5.5.5(a). 

NHTSA understands the symbols proposed in your correspondence to be separate from and additional to the required words or abbreviations discussed above. With this understanding, the two proposed symbols pictured in your correspondence would not be subject to the word height requirement laid out in FMVSS 135 S5.5.5(a), as they would be considered additional words or symbols used for clarification purposes. Accordingly, neither the symbols, nor the letters that are part of the symbols, would be required to be at least 3.2 mm. 

However, if a vehicle does not use Table 1’s required words or abbreviations as a telltale for the item in question, and instead only uses a symbol that does not contain the required words or abbreviations, then the vehicle does not meet the requirements of FMVSS 101 S5.2.1, regardless of the height of the symbol or the letter(s) in the symbol. 

Finally, we note that, as discussed above, one permissible telltale for an anti-lock brake system malfunction is the abbreviation “ABS.” Accordingly, if the symbol pictured in your letter that includes the letters “ABS” is the only telltale used in a vehicle to indicate an antilock system brake malfunction, then the letters “ABS” in that symbol must meet the 3.2 mm minimum height requirement in FMVSS 135 S5.5.5(a). It would not be sufficient for the symbol as a whole to meet this height requirement, because S5.5.5(a) specifically requires the “words” to meet the requirement. 

I hope this information is helpful. If you have any further questions, please feel free to contact Natasha Reed of my staff at this address or at (202) 366-2992.

Sincerely,
Adam Raviv
Chief Counsel

Dated: 6/7/24
Ref: Standard No. 135