Interpretation ID: 22311new

Mr. Takashi Yoshie
General Manager
Toyota Technical Center, USA, Inc.
1850 M Street, NW
Washington, DC 20036

Dear Mr. Yoshie:

This is in response to your letter requesting an interpretation of Federal Motor Vehicle Safety Standard (FMVSS) No. 135, Passenger Car Brake Systems. Specifically, you state that you believe that S7.11, Brake Power Unit or Brake Power Assist Unit Inoperative (System Depleted), of Standard No. 135 does not require a human test driver to apply the brake during the test, and that a brake testing unit may be used by vehicle manufacturers for in-house testing and by NHTSA for compliance testing. The issues you raise are addressed below.

By way of background information, the National Traffic and Motor Vehicle Safety Act (49 U.S.C. Chapter 301) authorizes the National Highway Traffic Safety Administration (NHTSA) to issue safety standards applicable to new motor vehicles and items of motor vehicle equipment. NHTSA, however, does not approve motor vehicles or motor vehicle equipment, nor do we endorse any commercial products. Instead, the Safety Act establishes a "self-certification" process under which each manufacturer is responsible for certifying that its products meet all applicable safety standards.

We expect manufacturers to have some basis for their certification that a product complies with all applicable safety standards. This does not necessarily mean that a manufacturer must conduct the specific tests set forth in an applicable standard. Under current law, certifications may be based on, among other things, engineering analyses, actual testing, or computer simulations. Whatever the basis for certification, however, the manufacturer must certify that the product complies with a standard as it is written; i.e., that the vehicle will pass all applicable requirements if it is tested according to the standard's test conditions and other specifications.

Standard No. 135 specifies requirements for service and parking brake systems in order to ensure safe braking performance under normal and emergency driving conditions. It applies to passenger cars manufactured for sale in the United States on or after September 1, 2000, and to multi-purpose passenger vehicles, trucks, and buses with a gross vehicle weight rating (GVWR) of 3,500 kilograms (7,716 pounds) or less manufactured on or after September 1, 2002. The test procedures for vehicles equipped with one or more brake power units or brake power assist units

are set forth in S7.11 of the standard. These procedures specify that the load applied to the brakes is less than or equal to 500 N (112.4 pounds).

You state that Toyota has observed large testing variability between test drivers with respect to the load that is applied during the S7.11 test. To reduce this variability, Toyota has developed a brake testing unit (BTU) that applies a pre-determined load onto the brake pedal to allow for consistent and repeatable brake applications. You state that for purposes of the test specified in S7.11, the BTU can be programmed to apply a load of, for example, 490 N to ensure that the 500 N limit is not exceeded. You believe that the use of a BTU complies with the test procedures set forth in S7.11 of Standard No. 135.

You are correct that Standard No. 135 does not specify that a human test driver be used to apply the brake during the S7.11 test. I note, however, that NHTSA does not currently have any plans to use a BTU in conducting compliance tests.

If you have any further questions regarding this matter, please contact Mr. Dion Casey in my office at (202) 366-2992.

Sincerely,

John Womack
Acting Chief Counsel
ref:135
d.3/8/01