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Interpretation ID: 571.108--Supplement beam--Boykin--16-0884

Mr. Marcus Boykin

B-G Innovative Safety Systems, LLC

79 Pasture Road

Lexington, TN 38351

Dear Mr. Boykin:

This responds to your letter asking about the application of Federal Motor Vehicle Safety Standard (FMVSS) No. 108, “Lamps, reflective devices, and associated equipment,” to a lighting system your company has developed.  In your letter and phone conversation with John Piazza of my staff, you describe your product as “an auxiliary vehicle lamp operating system” for use both as original equipment (OE) and as aftermarket equipment.

You state that your product, which adapts to the existing headlight wiring harness, provides a supplemental lower beam from the existing upper beam when the lower beam fails.  We understand that, when the lower beam is not in a failed state, the headlight system, controls, and telltales function normally.  If the lower beam is selected and has failed or does fail, your system provides a supplemental lower beam from the existing upper beam.  You state that the lighting on the converted upper beam is “diffused down to the same output illumination as” the lower beam.  If the upper beam is selected, the upper beam will continue to function normally. 

We further understand that, with respect to the OE version of your product, you contemplate a dashboard warning to warn the driver that the normal lower beam is not functioning.  In the aftermarket version of your product, once the vehicle’s lower beam has failed and your device is providing a supplemental lower beam, every time the engine is started the headlights will flash three times to warn the driver that the original equipment lower beam is not operating and that your device is providing a supplemental lower beam.  You state that you are seeking “interpretation and approval” of your device.

As we explain below, while NHTSA does not provide approvals of motor vehicles or motor vehicle equipment and does not make compliance determinations outside of an agency compliance proceeding, we are able to provide you with our interpretation of how NHTSA’s statute and regulations would apply to your product as you have described it to us.  We believe that your product would be considered supplemental lighting.  As such, it may be installed as original equipment as long as it does not impair the effectiveness of any required lighting.  If your product is offered as aftermarket equipment, it would not be directly subject to FMVSS No. 108 but would be subject to the Safety Act’s make inoperative prohibition.

Background

The National Highway Traffic Safety Administration (NHTSA) is authorized by the National Traffic and Motor Vehicle Safety Act (Safety Act), 49 U.S.C. Chapter 301, to issue Federal motor vehicle safety standards that set performance requirements for new motor vehicles and new items of motor vehicle equipment.  NHTSA does not provide approvals of motor vehicles or motor vehicle equipment and does not make determinations as to whether a product conforms to the relevant FMVSS outside of an agency compliance proceeding.  Instead, the Safety Act requires manufacturers to self-certify that their products conform to all applicable FMVSSs.  Manufacturers must also ensure that their products are free of safety-related defects.

This letter provides you with our interpretation of how the statute and regulations administered by NHTSA would apply to your product as you have described it to us, based on our understanding of the information provided.  This is not an “approval” of your product.

Vehicle lighting sold as OE is regulated under FMVSS No. 108.  (All references in this letter are to subsections of FMVSS No. 108 unless otherwise noted.).  FMVSS No. 108 requires vehicles to be equipped with certain types of lamps (known as “required” lamps), which must meet very specific and detailed performance standards.[1]  All other lamps are considered “supplemental” lamps.[2]  Unlike OE required lamps, OE supplemental lamps are not required to meet any specific performance requirements.  However, they are required to comply with certain generally-applicable provisions of FMVSS No. 108.  One of these provisions is set forth in S6.2.1, which states: “No additional lamp, reflective device, or other motor vehicle equipment is permitted to be installed that impairs the effectiveness of lighting equipment required by this standard.”

Both OE and aftermarket vehicle lighting are subject to the Safety Act’s “make inoperative” prohibition (49 U.S.C. § 30122), which prohibits a manufacturer, distributor, dealer, rental company, or motor vehicle repair business from knowingly making inoperative any part of a device or element of design installed on or in a motor vehicle or motor vehicle equipment in compliance with an applicable FMVSS.  While this “make inoperative” prohibition does not apply to individual vehicle owners, NHTSA encourages vehicle owners not to remove or otherwise tamper with vehicle safety equipment.  Also, any modifications made by a vehicle owner would have to comply with applicable state law. 

Discussion

FMVSS No. 108 requires vehicles to be equipped with one of several permissible headlighting systems.  Headlighting systems are comprised of headlamps and associated hardware.  The purpose of headlighting is primarily to provide forward illumination.[3] 

The threshold issue presented by your request is whether your product is part of the required headlighting system, and thus subject to FMVSS No. 108’s requirements applicable to headlighting systems or, instead, supplemental lighting that is regulated by FMVSS No. 108’s impairment provision.   

In determining whether lighting equipment that provides forward illumination is part of the required headlighting system or, instead, supplemental lighting, NHTSA looks at several factors.  These include: (1) where the lamp directs its light; (2) whether it uses a headlamp replaceable light source to emit a beam that provides significantly more light flux than supplemental cornering lamps or fog lamps; (3) whether the lamp is intended to be used regularly, or is limited to more narrow driving conditions and situations; (4) whether the vehicle’s complete lighting system, not including the lamp in question, would include all of the forward lighting equipment required by FMVSS No. 108;  (5) whether there is a manual on/off switch; and (6) whether the lighting feature is one that activates only upon the failure of an element of the required headlighting system and acts as a temporary backup of that lighting element.[4] 

The last of these factors is most relevant to your product.  Prior agency interpretations have found that a lighting feature that activates an upper beam light source when the lower beam fails or a lower beam headlamp upon the failure of an upper beam headlamp is supplemental lighting.[5]  The system you describe activates a back-up beam only upon the failure of the required lower beam.  Accordingly, we believe it is supplemental lighting. 

Since you contemplate selling your supplemental lighting device as original and/or aftermarket equipment, we will consider the requirements affecting each of these.

Supplemental lighting installed as original equipment

Supplemental lighting installed as OE (i.e. before sale to first purchaser other than for resale) is permitted if the lighting does not impair the effectiveness of any lighting equipment required by FMVSS No. 108 (S6.2.1).  If you are the manufacturer of original lighting equipment required by FMVSS No. 108, but not the manufacturer of the vehicle on which it is installed, the vehicle manufacturer, and not you, has the legal responsibility under the Safety Act to certify that the vehicle complies with FMVSS No. 108 and all other applicable FMVSSs.  Accordingly, the vehicle manufacturer must certify that supplemental lighting installed as OE complies with S6.2.1.  Effectiveness may be impaired if, among other things, the device creates confusion with the signal sent by another lamp, or functionally interferes with it, or modifies its candlepower to either below the minima or above the maxima permitted by the standard.[6] 

Table XIX has specific photometry requirements (maxima and minima) for lower beams.  Activation of an upper beam light source when a lower beam source fails raises considerations of glare.  The lower beam maxima are meant to ensure that other roadway users are not glared.  If your device produces a supplemental beam that exceeds the lower beam photometric maxima, we would consider that to impair the effectiveness of the headlighting system.  Accordingly, your device needs to modify the upper beam to ensure that the lower beam photometric maxima are not exceeded. [7]  Because your device is supplemental lighting, it would not be required to provide sufficient illumination to meet or exceed the photometric minima required for a lower beam headlamp.  However, we note that by reducing the output illumination of the upper beam to that of the lower beam, the reduced upper beam would provide only a limited amount of illumination that may not be sufficient to usefully illuminate the road. 

For your information, we also point out below several other requirements of which you should be aware in designing and manufacturing your product.  (Note that it is the responsibility of manufacturers, and not NHTSA, to identity all FMVSSs applicable to their products and certify the compliance of their products with the standards.)

 

  • Your product must not interfere with the activation and operation of the upper beam.    
  •  It may not impair the effectiveness of the upper beam headlamp indicator required by S9.5.  When your device is providing a supplemental lower beam, it should do so in a way that the upper beam indicator is not activated.  Also, when the driver (or vehicle, if it has a semiautomatic headlamp beam switching device, or automatic headlights) has activated the upper beams, the upper beams must be activated and the upper beam indicator must be activated.  
  • S9.4 requires that “the lower and upper beams must not be energized simultaneously except momentarily for temporary signaling purposes or during switching between beams.” 
  • The headlamps must be steady burning, except that they may be flashed for signaling purposes.[8]  We would not consider your system’s momentary flashing function as violating this requirement because it is similar to a signaling function and would not be likely to confuse other motorists because it only flashes upon start-up.  
  • The device generally should not function in such a way that it would be likely to confuse other motorists (for example, it should not mask the ability of other drivers to perceive the front turn signal).
  • If a telltale or control is offered as original equipment, it must comply with any relevant requirements in FMVSS No. 101, “Controls and displays.”

 

We wish to point out that Table I-a requires that “[t]he wiring harness or connector assembly of each headlighting system must be designed so that only those light sources intended for meeting lower beam photometrics are energized when the beam selector switch is in the lower beam position[.]”  Although it may appear that a device such as yours might not meet this requirement, NHTSA has interpreted the requirement otherwise. 

This issue arises if the lower beam is activated (with the beam selector switch in the lower beam position) and then fails, after which a system (such as yours) activates a modified upper beam as a backup lower beam.  If the backup lower beam utilizes upper beam light sources that are not normally used for meeting lower beam photometrics, the backup lower beam might be viewed as violating this requirement.[9]  However, prior interpretations have concluded that this Table I-a requirement does not apply to a failure condition in which a supplemental beam supplements a failed lower or upper beam, assuming the supplemental light does not otherwise impair the effectiveness of any required lighting.[10]  Applying that line of reasoning, we believe that your system would not create a noncompliance with the Table I-a requirement.

Supplemental lighting offered and installed as aftermarket equipment

Supplemental lighting offered as aftermarket equipment (accessory lighting) is not directly subject to FMVSS No. 108, which applies only to original equipment and lighting equipment manufactured to replace original lighting equipment required by FMVSS No. 108.  Section 30122 of the Safety Act, however, prohibits a manufacturer, distributor, dealer, rental company, or motor vehicle repair business from knowingly making inoperative, in whole or in part original required lighting equipment.  In applying the make inoperative prohibition to accessory lighting we typically ask whether the accessory lighting would impair the effectiveness of any required lighting.  Generally, if an item of accessory lighting would not be permitted as original equipment, commercial entities will not be permitted to install the lighting as an aftermarket accessory for a vehicle in use.  Thus, the make inoperative analysis is generally the same as the impairment analysis we applied above in the context of supplemental lighting installed as original equipment.  We observe that, due to varying headlamp designs throughout the vehicle fleet, there may be potential compatibility issues with the product you describe and certain vehicles.  In addition, manufacturers of aftermarket lighting accessories are subject to the Safety Act’s defect notification and remedy requirements discussed above.    

We also note that manufacturers of equipment to which an FMVSS applies must meet the manufacturer identification requirements set out in 49 CFR Part 566.  For these and other requirements, you may consult NHTSA’s New Manufacturers Handbook, available at https://www.nhtsa.gov/sites/nhtsa.dot.gov/files/manufacturer_information_march2014.pdf.

If you have any further questions, please contact John Piazza at (202) 366-2992.

Sincerely,

Jonathan Morrison

Chief Counsel

Dated: 5/17/19

Ref: FMVSS No. 108


[1] The standard’s performance requirements also apply to lamps that are “for replacement of like equipment on vehicles to which this standard applies.”  On a related matter, we note that you state that “drivers with a failed light are out of compliance.”  This is incorrect, as FMVSS No. 108 does not regulate lighting in use.  Therefore, if a headlamp fails in operation, the vehicle is not “out of compliance” with the Federal standard (state laws may apply to in-use performance).

[2] NHTSA also uses the term “auxiliary” lamps.

[3] S4 (“Headlamp means a lighting device providing an upper and/or a lower beam used for providing illumination forward of the vehicle.”) (Formatting in original.)

[4] Letter to [Redacted] (Jan. 21, 2004) ((1)-(5)), available at https://isearch.nhtsa.gov/files/swivelinglamp.3.html (last accessed June 20, 2018); letter to L. W. Camp, Ford Motor Company (July 15, 1998) ((6)), available at https://isearch.nhtsa.gov/files/18080.ztv.html (last accessed June 20, 2018). 

[5] Letter to L. W. Camp, supra (lower beam backing up upper beam); letter to Ian Goldstein, Safe Passage Technologies (July 21, 1998) (upper beam backing up lower beam), available at https://isearch.nhtsa.gov/files/18164.ztv.html.

[6] See, e.g., letter to Byung M. Soh, Target Marketing Systems, Inc. (Sept. 13, 1988), available at https://isearch.nhtsa.gov/gm/88/nht88-3.100.html (last accessed June 20, 2018).

[7] Letter to Ian Goldstein, supra (“Because headlamps are primarily operated on the lower beam, activation of an upper beam light source when a lower beam source fails raises considerations of glare . . . the upper beam in this instance ideally should be activated at a markedly reduced intensity such that it does not impair the effectiveness of required lighting devices [S6.2.1], or, more specifically, that, as a lower beam substitute[] it does not compromise turn signal visibility.”)

[8] Table I-a.

[9] Whether this would occur depends on the design of that particular headlighting system.  For example, this would not be the case if the headlighting system used the same light sources for both the lower and the upper beams.

[10] Letter to L. W. Camp, supra (lower beam supplementing failed upper beam).  See also letter to Ian Goldstein, supra (modified upper beam supplementing failed lower