Interpretation ID: nht73-5.20

DATE: 01/15/73

FROM: AUTHOR UNAVAILABLE; Richard B. Dyson; NHTSA

TO: Nissan Motor Company

TITLE: FMVSS INTERPRETATION

TEXT: This is in reply to your letter of December 14, 1972, concerning the acceptability, under S7.4 of Standard 208, of a time delay device in a belt interlock system.

As described in your letter, the delay device would permit an occupant who has operated the belt in the correct sequence to lift off the seat while buckled for a brief period before attempting to start the vehicle. Under S7.4 as presently constituted, this action by the occupant would result in the belt's being buckled before the seat is occupied. The occupant would therefore have to unbuckle the belt and rebuckle before starting the car. A time delay device, in short, would not be allowable.

We make no comment that this situation is desirable or undesirable, but it is, however, required by the language of S7.4.

NISSAN MOTOR CO., LTD.

December 14, 1972

Lawrence R. Schneider National Highway Traffic Safety Administration

This is to request your interpretation of MVSS 208, S7.4, Belt Interlock System.

QUESTION 1

Would a belt interlock system utilizing a time delay device, which works as shown in the enclosed illustration, in order to avoid the following situation meet MVSS 208, S7.4?

SITUATION

If a front seat occupant, after buckling his seatbelt, were to move in such a way as to lift himself from the seat for any reason before starting the engine, that person would be required to unbuckle and rebuckle in order to start the engine. This situation is not only inconvenient to the customer but also may alarm him as he may not realize why the engine does not start although he has done the proper process.

QUESTION 2

Should the abovementioned interlock system meet MVSS 208, how many seconds (3 or 5) delay ("t" see illustration) will be acceptable?

Due to a very short lead time a prompt reply would be greatly appreciated.

Satoshi Nishibori Engineering Representative Liaison Office in USA

FUNCTION OF TIME DELAY DEVICE

(Graphics omitted)