Interpretation ID: nht88-1.22
TYPE: INTERPRETATION-NHTSA
DATE: 02/01/88
FROM: AUTHOR UNAVAILABLE; Erika Z. Jones; NHTSA
TO: Jaguar Cars, Inc.
TITLE: FMVSS INTERPRETATION
TEXT:
C.D. Black, Engineering Manager Legislation, Compliance Product Development 600 Willow Tree Road Leonia, NJ 07605
Dear Ms. Black:
This is in reply to your letters of June 8 and October 17, 1987, with respect to an electrically-operated headlamp leveling system that Jaguar intends to offer on passenger cars beginning with the 1989 model year. Such a device is required by EEC regulat ions. You have informed us that the system does not allow lamps to be adjusted above the "zero" position, only downward to compensate for rear end loading of the vehicle. There is no provision for automatic return to the "zero" position when the engine i s turned off. Further, there will be no indication to the driver from the vehicle instrumentation that re-aim is necessary when the headlamps are adjusted downward. You have concluded, for the six reasons given in your letter of June 8 that "no aspect of FMVSS 108 . . . is contravened by this proposed installation."
The sole restriction that Standard No. 108 imposes upon an item of motor vehicle equipment not covered by the standard but which a manufacturer wishes to add to a vehicle as original equipment is that it not impair the effectiveness of the lighting equip ment that the standard requires (S4.1.3). If a manufacturer concludes that the unrequired equipment would not impair the effectiveness of the required lighting equipment, it may certify that the vehicle complies with Standard No. 108. Based on our unders tanding of your system, it does not appear to impair the effectiveness of the required equipment. However, we urge you to consider the possible consequences if the driver forgets to return the system to the "zero" position from either of the two adjustme nt positions. These possibilities are a concern because the system does not automatically return to that position, and no warning is provided to the driver that the headlamps are not in their original design position. On the other-hand, if properly used, the system could enhance headlighting effectiveness by ensuring that the headlamp provides the same lighting performance under all conditions of vehicle load.
We hope the information is helpful.
Sincerely,
Erika Z. Jones Chief Counsel
June 8, 1987
Ms. Erika Z. Jones, Chief Counsel National Highway Traffic Safety Administration 400 Seventh Street SW Washington, D.C. 20590
REQUEST FOR INTERPRETATION FMVSS 108 DRIVER ADJUSTMENT OF PASSENGER CAR HEADLAMPS
Dear Ms. Jones:
Jaguar Cars Ltd. of Coventry, England, manufactures passenger cars for worldwide markets. For UK and European road vehicles of all types it will be required, by EEC Directive 76/756 (as amended) Paragraph 4.2.6, to fit a system for maintaining headlamp d ip beam (passing beam) vertical alignment. If this is not achieved by power operated suspension levelling, then either an automatic lamp-levelling system or a control operable from the driving seat must be provided.
Jaguar will fit an electrically operated lamp-levelling system, operable from the drivers seat, to the XJ-S model range on all cars for the United Kingdom and for Europe from Job 1 1989 model year. Jaguar would like to fit this system to cars supplied fo r the USA market.
Jaguar believes that this will not contravene or compromise any aspect of compliance with FMVSS 108 for the following reasons:
1. In a front-engine passenger car, the only adjustment required after the initial aim in the "driver only" condition is downward. (This may not be valid for rear engine cars or for heavy trucks).
2. The lamps will be compatible with the use of mechanical aimers as defined in FMVSS 108 and the sub-referenced SAE J.602. New semi-sealed light units for the USA models will conform with all applicable requirements of FMVSS 108. (Distinct conditions of light units will be used for U.S. and for Europe but they will be designed to fit commonised mountings and therefore will enable use to be made of the lamp levelling feature.)
3. The lamp mounting will be designed to meet the torque deflection test of SAE J.580.
4. A mechanical adjustment facility for manufacturing tolerances and an initial alignment will be fitted to each lamp and will be operable in the manner required by SAE J.580.
5. Subsequent to the initial alignment as defined in lighting inspection code SAE J.599, the only adjustment operable from the driving seat will be downward. Because the lamp provides both passing and driving beams this will enable the driver to adjust t he beams downward if necessitated by heavy rear seat, trunk, or trailer hitch loading. It is impossible to adjust the beams to a higher position than the datum setting by the operation of the control from the drivers seat.
Even if the driver does not use the control under the conditions outlined above, then the dazzle problem would never be worse than that created by conventionally mounted lamps. What the lamp levelling system would provide is the opportunity to eliminate dazzle that would otherwise occur.
6. Jaguar will explain in the owner literature the correct use of the control by the driver. Jaguar will also instruct dealers and servicing outlets of the need to zero the drivers control before checking or adjusting beam alignment.
For the foregoing reasons, Jaguar believe that no aspect of FMVSS 108 or the subreferenced SAE standards is contravened by this proposed installation. However, because of design and manufacturing leadtimes we request your confirmation that our interpreta tion is correct.
We believe we have explained all relevant features of the system but if further information or clarification is required, please contact me by telephone.
Sincerely,
C.D. Black CDB:as Engineering Manager Legislation, Compliance, Product Development