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Interpretation ID: Ponziani

Mr. Richard L. Ponziani

President

RLP Engineering

1958 Home Path Court

Centerville, OH 45459

Dear Mr. Ponziani:

This responds to your letter requesting clarification regarding how Federal Motor Vehicle Safety Standard (FMVSS) No. 108, Lamps, Reflective Devices, and Associated Equipment, applies to your product, which is referred to as an Electronic Intelligent Turn Signal System in the technical paper accompanying your letter. You described your product as a turn signal system that uses existing vehicle computers and wheel speed sensors to determine a situation appropriate shut off point, which you believe offers a safety improvement over current, mechanical turn signal operating units on passenger vehicles. Your letter stated that by combining steering wheel angle and steering wheel rotation data with other measures such as vehicle yaw and travel distance, your system may prevent instances of turn signal miscommunication, thereby increasing safety. Specifically, you cited examples in which the driver jars the steering wheel and the turn signal shuts off prematurely or lane change maneuvers where the steering wheel rotation is not sufficient to trigger turn signal cancellation. Although we have not examined your product, based on the information you have provided to the agency and the analysis below, we have concluded that your product would comply with the standard, provided that all of the other requirements of FMVSS No. 108 related to turn signals continue to also be met.

By way of background, the National Highway Traffic Safety Administration (NHTSA) is authorized to issue FMVSSs that set performance requirements for new motor vehicles and items of motor vehicle equipment (see 49 U.S.C. 30111 and 49 CFR Part 571). NHTSA does not provide approvals of motor vehicles or motor vehicle equipment. Instead, manufacturers are required to self-certify that their products conform to all applicable safety standards that are in effect on the date of manufacture, before they can be offered for sale (see 49 U.S.C. 30115 and 49 CFR Part 567). FMVSS No. 108 sets forth the requirements for both new and replacement motor vehicle lighting equipment. NHTSA selects a sampling of new vehicles and equipment each year to determine their compliance with applicable FMVSSs. If our testing or examination reveals an apparent noncompliance, we may require the manufacturer to remedy the noncompliance, and may initiate an enforcement proceeding if necessary to ensure that the manufacturer takes appropriate action.

Our statute (49 U.S.C. 30101 et seq.) prohibits any person from selling any new vehicle that does not comply with all applicable Federal safety standards (see 49 U.S.C. 30112). After the first sale of the vehicle, manufacturers, distributors, dealers, and repair businesses are prohibited from knowingly making inoperative any device or element of design installed on or in a motor vehicle in compliance with an applicable FMVSS. In general, the make inoperative prohibition (49 U.S.C. 30122) requires businesses that modify motor vehicles to ensure that they do not remove, disconnect, or degrade the performance of safety equipment installed in compliance with applicable standards. The make inoperative provision does not apply to owners modifying their own vehicles, but we urge owners not to degrade the safety of their vehicles.

Turning to the specific issues raised by your letter, FMVSS No. 108 sets forth requirements for turn signal lamps in light vehicles. First, Table 3, Required Motor Vehicle Lighting Equipment, of FMVSS No. 108 specifies that each passenger car, motorcycle, multipurpose passenger vehicle (MPV), truck, bus, and trailer of less than 80 inches (2032 mm) in overall width must be equipped with two amber turn signals at or near the front of the vehicle and two red or amber turn signals at or near the rear of the vehicle (note that trailers only require two red or amber turn signals to the rear); Table 3 also requires those vehicles (other than trailers) to be equipped with a turn signal operating unit[1] and a turn signal flasher. Standard No. 108 also specifies other turn signal lamp requirements, including ones pertaining to location, dimensions, and photometric output. However, we will not discuss those provisions in detail, because your submissions do not suggest that your product would impact these characteristics of the turn signals, but would instead be limited to their operation (i.e., the point at which the turn signal would be switched off in the course of a turning maneuver).

The provision of particular relevance here is paragraph S5.1.1.5 of FMVSS No. 108, which provides: The turn signal operating unit on each passenger car, and multipurpose passenger vehicle, truck, and bus less than 80 inches in overall width shall be self-canceling by steering wheel rotation and capable of cancellation by a manually operated control. As we pointed out in an April 2, 1986 letter of interpretation to Mr. Jacques Delphin, there are no performance requirements for the self-cancelling feature, so the agency concluded that the aftermarket device in question which cancels turn signal indicators immediately upon the completion of a turn would not impair the effectiveness of the turn signal operating unit or create a noncompliance with Standard No. 108. However, in a May 30, 1997 letter of interpretation to Mr. Reggie Lawrence, we concluded that an aftermarket Blinker Delay System that would prevent the automatic cancellation of the turn signal system for three to four seconds after the front wheels of a towing vehicle have been straightened (to indicate that a turn has not been completed) would create a noncompliance with Standard No. 108, by defeating the vehicles attempt to self-cancel the turn signals operation by steering wheel rotation. These letters are consistent in light of the provision in paragraph S5.1.3 of the standard, which provides, No additional lamp, reflective device or other motor vehicle equipment shall be installed that impairs the effectiveness of lighting equipment required by this standard. Thus, an aftermarket device which accelerates self-cancellation of turn signal operation immediately after a turn is consistent with the standard, but one which delays self-cancellation is not.

However, if your product is an original equipment (OE) turn signal system, which provides a control unit with a complete logic for self-cancelling turn signal operation (as compared to a supplemental system which changes the operation of an existing system), we conclude that it would be permissible under FMVSS No. 108. As described, your system evaluates driver steering inputs, as well as a variety of other information provided by vehicle wheel speed sensors, to determine the appropriate point for turning off the turn signal. (We note that your technical paper also states that your system would include a button allowing the driver to cancel the turn signal event at any time, thereby meeting the second requirement of paragraph S5.1.1.5.) Therefore, because the standard does not specify precisely when cancellation must occur (and based on our understanding that steering wheel rotation would be a triggering element each time the system does cancel the turn signal), we conclude that an OE Electronic Intelligent Turn Signal System as you have described would meet the requirements of FMVSS No. 108, provided that all of the standards other relevant requirements for turns signal are met.

If you have further questions, please feel free to contact Eric Stas of my staff at this address or by telephone at (202) 366-2992.

Sincerely,

Anthony M. Cooke

Chief Counsel

ref:108

d.3/22/07



[1] A turn signal operating unit is defined as that part of a turn signal system by which the operator of a vehicle causes the signal units to function (see Society of Automotive Engineers (SAE) standard SAE J589, Turn Signal Operating Units (rev. April 1964). Table 3 of FMVSS No. 108 incorporates SAE J589 (rev. April 1964) by reference, which includes a durability test for the turn signal system.