Philips Research Lab Aachen
P. O. Box 1980
Dear Mr. Halfmann:
This responds to your request for an interpretation of Standard No. 124, Accelerator control systems. You note that the Standard is "well adapted" to mechanically driven throttle plates, but not to electronically operated ones. You ask for an interpretation of how S5.1 of Standard No. 124, that specifies "at least two sources of energy capable of returning the throttle to the idle position," applies to electronic systems.
In an interpretation letter of August 8, 1988 to Isuzu (copy enclosed), the National Highway Traffic Safety Administration (NHTSA) interpreted Standard No. 124 to apply to electronic accelerator control systems. Among other matters, Isuzu described what it considered to be the "two sources of energy" that were capable of returning the throttle to the idle position. Based on the Isuzu's information, NHTSA gave an interpretation as to whether Isuzu's system met S5.1 of Standard No. 124.
As NHTSA did for Isuzu, if you would provide specific information about Philips' electronic acceleration control system, we will address whether the system meets S5.1 or any other part of Standard No. 124.
NHTSA has announced that it is considering amending Standard No. 124 to include requirements specific to electronic accelerator control systems. In a Federal Register notice of December 4, 1995 (60 FR 62061, copy enclosed), NHTSA noted that the standard was last amended in 1973, when only mechanical systems were common on motor vehicles. Although the comment deadline has passed, your company may submit comments on the issues raised in the notice. Any further actions NHTSA may take to amend Standard No. 124 will be announced in the Federal Register.
I hope this information is helpful. If you have any other questions, please feel free to contact Dorothy Nakama of my staff at (202) 366-2992.
Samuel J. Dubbin