Interpretation ID: nht72-3.45
DATE: 08/23/72
FROM: AUTHOR UNAVAILABLE; Richard B. Dyson; NHTSA
TO: Fairchild Semiconductor
TITLE: FMVSS INTERPRETATION
TEXT: This is in reply to your letter of July 26, 1972, on the subject of the situations in which S7.4.3 of Motor Vehicle Safety Standard No. 208 permits operation of the engine starting system, notwithstanding the ignition interlock requirements of S7.4.1 of the standard.
Your first question is whether the engine may be restarted if the ignition switch is turned off after the driver has left the seat. Our reply is that restart would not be permitted except within a period of three minutes after the switch has been turned off. There is no sequential relationship between the operation of the switch and the driver's leaving the seat, so that the starting system will have to become inoperable if the driver has left the seat and has turned the ignition off, regardless of whether he turned the switch before or after leaving the seat.
Your second question is whether the engine may be restarted if the ignition switch is turned off, then on, and then the driver leaves his seat. Our reply is again that restart would not be permitted. S7.4.3 refers to operation "if the ignition has not been turned off". Once the ignition has been turned off, turning it on again will not revive the restart mode unless the engine is actually started again and then stopped with the ignition "on".
We have forwarded your check for a Federal Register subscription to the Superintendent of Documents. Enclosed you will find a copy of Notice 20, as you requested.