What qualifies you to give legal advice?
Welcome to the board, Mr. or Ms. new poster. Please take a few deep breaths and adjust your tone and attitude -- do a little more listening and a little less mouthing off, at least at first.
You give the appearance of speaking English well enough that you probably know making a post on a web board identifying an illegitimate and illegal lighting component as illegitimate and illegal isn't actually anything like "giving legal advice", so let's dial down the overheated hype.
I have read why its a bad idea in the sticky
Good! Sometimes new posters who barge onto this board shouting about how wrong stuff is on here will also fail to actually read relevant content. So good on you for having made some effort. Thanks for that.
but that thread is four years old now
...and still every bit as correct as it was on the day it was written.
I have not found this text though have looked though many pages of the laws.
You haven't looked at the right pages, and you haven't understood those pages you have read. It looks like you're crowing about having not found any text that reads
LEDs may not be used as replacements for halogen bulbs in headlamps. Which you're not going to find, because that's not how technical regulations are written.
This is the complete section dealing with light sources
Well, no. It's one part of one of the apposite chunks of statutory text.
Where is the law that states LED' are illegal as you claim?
Part of it is in the very first paragraph of the portion you quoted from Federal Motor Vehicle Safety Standard No. 108:
S11 Replaceable light source requirements. Each replaceable light source must be designed to conform to the dimensions and electrical specifications furnished with respect to it pursuant to part 564 of this chapter, on file in Docket No. NHTSA 98-3397
There are no retrofit LED bulbs that conform to the dimensions and electrical specifications for any halogen bulb type as specified in the
Part 564 docket.
LEDs are now the exact location and size of a halogen filament
Maybe in some cases, but that's only two of the many different light source parameters that have to be correct for the headlamp to comply with the law and work in an effective, safe, and legal manner when installed in a headlamp. And even if the emitters on an "LED bulb"
are the same size and in the same location as a filament would be, they're still not the same shape or orientation because there are no cylinder-shaped LEDs, and the backer boards and heat sinks create significant shadows where there's supposed to be light.
So that's one big reason why "LED bulbs" fail to comply with Federal Motor Vehicle Safety Standard No. 108.
Also, separately, there is the issue of selling vehicle equipment which, when installed, takes the vehicle out of compliance with any applicable Federal Motor Vehicle Safety Standard. A good example of that is bulbs for lamps other than headlamps: they aren't directly regulated by FMVSS 108 (or any other), but if I sell bulbs that physically fit in the turn signals, brake lights, etc of a vehicle certified as compliant with all applicable FMVSS requirements, and my bulb causes those lights to no longer perform in a compliant manner, I can wind up wearing significant legal liability for it. The same applies to "LED bulbs" for headlamps: even if I magically manage to come up with an LED bulb that complies with all the requirements for one of the halogen bulb types in Part 564, if it changes the performance of a headlamp in ways that make the beam pattern noncompliant, my bulb is still illegal.
S11.4.1 Each replaceable light source must be designed to conform with the performance requirements of the deflection test and pressure test requirements of S14.7.
Few or none of the "LED bulbs" on the market comply with this provision (and most of them couldn't pass if they were tested).
S11.4.2 Replaceable light sources must be designed to conform with the requirements of section VII of appendix A of part 564 of this chapter, or section IV of appendix B of part 564 of this chapter, for maximum power and luminous flux when test by the procedure of S14.7.3.
Ditto here: most or all of the "LED bulbs" on the market can't meet these requirements.
But let's say a genie appeared one night while you were washing dishes and happened to rub a particular saucepan just right, and granted you three wishes, and you wished for those cylinder-shaped LEDs, and *POOF* now you have them. You use them to build an LED bulb that complies with every requirement for the type of halogen bulb we intend to replace (H11, or 9006, or whatever). You build the LED bulb to pass the deflection and pressure test requirements of S14.7. You specify the emitters so the amount of light is the same as the halogen bulb. You used one of your other genie-wishes to make these cylinder-shaped emitters have extremely high luminous efficacy, say 500 Lm/W, so to get the 1000 lumens for the 9006 you need only a 2W device, so you can just have your cylinder-shaped emitter suspended by its lead wires in exactly, precisely the same place as a filament -- no backer board to cast shadows. The light distribution is truly an exact match for the halogen bulb. But you're
still not looking at a legal bulb, because there are requirements specific to LED lighting devices. They have to pass tests for output at a range of ambient temperatures, and for lumen maintenance with extended operation, because LEDs' output drops with increased temperature. These are challenging tests even for legitimate LED lamps without the constraints imposed by having to match the physical form factor of a halogen bulb, and those constraints make it even harder.
That said, there is hope on the horizon; eventually that "why it's a bad idea" post will have to be modified. Not tomorrow, but eventually. See
here.