Interpretation ID: nht78-2.12

DATE: 08/29/78

FROM: AUTHOR UNAVAILABLE; J. J. Levin, Jr.; NHTSA

TO: Cibie Corporation

TITLE: FMVSS INTERPRETATION

TEXT: This is in belated reply to your letter of December 15, 1977, requesting an interpretation of Federal Motor Vehicle Safety Standard No. 108, Lamps, Reflective Devices and Associated Equipment. Your request concerned the legality of installation on motor vehicles of remote manual or of automatic headlamp aiming equipment.

If a headlamp assembly meets the requirements of Standard No. 108 when installed with or without auxiliary means of aiming, we consider the assembly to be in conformance. Your device does not appear to impair the effectiveness of the required lighting equipment within the prohibition of S4.1.3, and either device that you described would apparently provide an additional safeguard against glare when the rear of the vehicle is heavily loaded.

SINCERELY,

CIBIE CORPORATION

Office of the Chief Counsel N.H.T.S.A.

December 15 1977

Dear Sir

Headlamp "Aim Correction"

Cibie Corporation is a Delaware Corporation, the American subsidiary of CIBIE PROJECTEURS of Bobigny, France. Cibie Projecteurs manufacturers automotive lighting equipment of every description: headlamps, fog and spotlamps, combination lamps, etc. In addition, headlamp aim correction units are manufactured for passenger cars.

In Europe, these aim correction units are referred to as headlamp levellers; this terminology may lead to confusion with suspension levellers in the United States, hence I have coined the name "aim correction units" in the absence of a recognized term.

The aim correction units manufactured by Cibie are of two types: manual and automatic. Both types are additional to the normal aim features of the headlamp system to which they are applied. That is to say, the correct aim of the headlamps is first established by means of a screwdriver adjustment made externally to the headlamp by a person standing at the front of the car. (Sometimes the screwdriver is not required, where the slotted-head screw has a finger-tip knob molded onto it, allowing the basic aim to be made with the fingers directly.)

The movement of the headlamps that is applied by the aim correction units to the basic correct adjustment is in a downward sense only, to compensate for a full luggage load in the trunk. Thus, the aim correction units cannot of themselves produce dazzle; however, failure by the driver to take advantage of them can allow dazzle to persist (due to luggage load) that could otherwise be removed by their use.

Dealing with the two types of aim correction unit, taking the manual type first: there are two types of manual aim correction unit, two-position and variable.

The earlier two-position type incorporates a cam in the headlamp mounting itself. A small lever, moved by hand, produces a downward correction of the headlamp aim; this lever is accessible by raising the engine hood of the car.

The later variable type incorporates a small piston unit and control knob under the instrument panel, operable from the driving seat. Hydraulic tubing connects the piston unit to a slave unit on each headlamp, lowering the headlamp aim by any desired amount within the design limits of movement. Again, the aim correction is downwards only.

The automatic aim correction unit incorporates hydraulic sensors on the vehicle suspension which, by means of hydraulic tubing and the same slave units, correct the headlamp aim downward without any action on the part of the driver. In the case of the automatic system, headlamp aim is also corrected dynamically for vehicle pitching movements as well as statically for luggage load.

These three types of aim correction unit have been in use in Europe for many years. The automatic unit is currently standard equipment on the Lancia Beta.

Council Directive 76/756 of the European Common Market now requires passenger cars to be fitted with headlamp aim correction units, operable from the driver's seat or automatic. Thus, it is entirely possible that European passenger car manufacturers may wish to export to the United States models of cars in which the European headlamps have been replaced with SAE sealed beams, in accordance with FMVSS 108, but still retaining the aim correction feature, whether manual or automatic.

Cibie Projecteurs, as manufacturer of the aim correction units, would wish to be in a position to advise its customers as to the eligibility of these units for importation into the United States.

Therefore, Cibie Corporation requests a legal opinion as to whether a passenger car that complies in all respects with FMVSS 108, but in addition is equipped with manual or automatic aim correction as described above, would be deemed still in compliance with FMVSS 108.

Inasmuch as the application of the Council Directive takes effect during 1978, the earliest possible answer to this enquiry would be greatly appreciated.

H J T YOUNG Vice President - Technical Affairs