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Interpretation ID: nht88-2.77

TYPE: INTERPRETATION-NHTSA

DATE: 07/20/88

FROM: C. S. ALLEN -- COMMANDER-DEPARTMENT OF CALIFORNIA HIGHWAY PATROL

TO: STEPHEN P. WOOD -- NHTSA RULEMAKING DIVISION

TITLE: NONE

ATTACHMT: DECEMBER 30, 1988 LETTER FROM JONES TO ALLEN

TEXT: This letter is to request an interpretation of the meaning of one sentence contained in Federal Motor Vehicle Safety Standard No. 102 (FMVSS 102).

This sentence, found in Title 49 of the Code of Federal Regulations (49 CFR) Part 571, Section 571.102 S3.1.3, states, "Starter interlock. The engine starter shall be inoperative when the transmission shift lever is in a forward or reverse drive positio n".

The California Highway Patrol has become aware that a major manufacturer of school buses, Crown Coach Incorporated, of 13799 Monte Vista Avenue, Chino, California 91710-5513, has been building vehicles equipped with automatic transmissions which, althoug h equipped with the interlock required by 49 CFR 571.102 S3.1.3, are also equipped, at the driver's position, with a momentary contact push-button switch, the purpose of which is to bypass the transmission neutral safety switch.

Mr. Greg Alvarez of my staff discussed the legality of this device with Mr. James Cowan, Director of Engineering at Crown Coach, Inc., by telephone on June 24, 1988. At that time Mr. Cowan stated his opinion that the bypass switch complied with FMVSS 10 2 because it was only an emergency feature, not intended to be used for routine engine starts. He stated that the only way the bus could be started with the transmission shift level in a forward or reverse drive position would be if the driver used both hands, one to operate the bypass switch to the right of the steering column, and the other to operate the regular starter key-type switch to the left of the steering column.

Mr. Cowan stated to this Department that this starter interlock bypass switch is regarded by Crown Coach as a safety feature, intended for emergency use in

the event that the bus engine dies at an inopportune moment, as when crossing a set of railroad tracks, or in case the neutral safety switch contacts fail to close upon selection of neutral range.

Pending your reply it is our position that the bypass switch renders buses equipped with automatic transmissions in violation of FMVSS 102 (and of an identical California state regulation). Crown Coach appears to be interpreting FMVSS 102 as meaning tha t the starter shall not be capable of being started from the driver's position with the transmission in gear unless the driver intends to do that.

As for the argument that the bypass switch allows for quick restarts on rail crossings or other dangerous locations, we feel that if the amount of time required to select neutral range, restart the engine and return to drive range is anticipated to be ex cessive, why not eliminate the neutral safety switch altogether? The driver would then be able to keep one hand on the steering wheel while restarting the engine with the transmission in gear. With Crown's present arrangement, a bus can be restarted in gear only by removing both hands from the steering wheel.

It is our belief that 49 CFR 571.102 S3.1.3 is intended to prevent motor vehicles equipped with automatic transmissions from being started in gear at any time. We would appreciate your earliest possible response to our request for an interpretation on t his matter, so that our inspectors and the engineering staff at Crown Coach, Inc. will have authoritative information on which to act.