Custom tail lights

[jdeez974]

Hi everyone, I am new here and created my account just so I can try and get some help with an idea I have for my truck.

I am of course in the custom auto scene, and recently thought of an idea that I think would work pretty well for my tail lights.

This will be my first full blown custom job using all LEDs and all the parts associated with them (out side of learning how LEDs work from an elemental point of view).

My idea will be to create a dual tail light for both sides. Each set will contain two sets of LEDs in a strip. Both sets will be able to light up as regular tail lights, get brighter when I push the brake pedal, when using turn signal both will be sequential from the inner body towards the fender wells, and when I put it in reverse I would like them to light up white.

Given what all that I would like them to do. I know I will need a set of red LEDs and a set of white LEDs to have the two separate functions. But here is a few things I am curious about and need help with:

1. these tail lights will in a straight line, and I’m thinking about 15" in length. How many LEDs should I use for this? Like I’m not sure how close they should be measurement wise from one LED to the next.
2. Is there/should I use a PCB board to set all of this up on and have my car’s wiring run to it and that board do basically all the work?
3. What all am I going to need other than a)LEDs of both colors b)resistors c)soldering equipment?

Thanks in advance for all of the help. I am not going to start this project for some time. So I have plenty of time to learn what needs to be done, and how to do it properly.

[Oli]

Rear ”lights" on vehicles almost always incorporate required reflectors visible to the rear and side that meet Dot requirements.
This is a 25-year-old answer that covers most of what you are trying to do by removing or altering the factory tail lights and the obstacles.
https://www.nhtsa.gov/interpretations/21575ztv#:~:text=Lamps%20incorporating%20white%20lenses%20and,meeting%20J578’s%20amber%20color%20specification.
Do you have any flashlight questions?

[raccoon]

Have a nice time here, jdeez974!

[jdeez974]

Wow, you’re a helpful one lol. The link you gave is fine, if this was a factory vehicle, following factory vehicle specs in which the DOT has established.

However, in this post, this is not the case. This is for a customized vehicle. That’s for the most part… for show.

One could further dive into the deep links of the dot and also explain that all tail lights must be at the highest point of your vehicles rear, and at the very far corners of both the left and right sides, and visible by x amount of distance away. But let’s be honest. Not a single DOT officer is going to pull anyone over for lack of red reflective tape inside a tail light housing, as long as the tail lights shine brightly in the color red. Not a faded shade of such, like pink, off white with a tinge of redtpink etc.

Also to give you a better idea i have attached an image to show the bases of what is currently legally allowed to drive with. My version will be similar but different. Notice the lack of red reflective-ness.

[Oli]

All right so you’re trying to claim that this is just for show but then you want to say it’s also legal. There’s a reason that magnetic minis went out of business. And that vehicle in Connecticut only got away with it for a while because Connecticut does not have a yearly or biannual safety inspection. I don’t know what state you’re in but that truck is not legal in any state in the US. I can see a couple of violations that have nothing to do with the lights. And the lights are not legal.

[L4M4]

Just an Idea, I would use a red COB strip: COB-LED-Streifenlicht, hohe Dichte, lineare Beleuchtung, 480/528 LEDs/m, flexibles Band, warm, natürliches Weiß, Rot, Blau, Grün, Dekor, DC12, 24 V - AliExpress 39
At least for the red - white will not be bright enough if you really want to use it. For show noone will care.

[jdeez974]

Thank you for the suggestion! I have looked into those. But im not sure if it would sequence like I’m wanting it to for my blinkers.

And as for the white, it wouldn’t have to be super bright. Because i mean, it’ll show the proper color when I’m in reverse, so people would get the idea. I would be more concerned with the brightness of the red for the regular running light part

[gravelmonkey]

Welcome to BLF!

Were you aware you posted in a sub-forum for lights one wears on one’s head?

Terminology contentious, for sure.

I’d have thought a car or electronics forum might be a better fit? I rarely see vehicle lighting discussed on here, we mostly power things with 1+ 3.7V cells.

I’m imagining a Audi style “chaser” indicator, plus ability to go white in reverse, this doesn’t seem extraordinarily complicated, are there no existing products already? I would assume it would be easier to modify something that already exists than to start from scratch.

[jdeez974]

I was not aware of that lol. I saw head light and was thinking vehicle lol, i appreciate the heads up! I did look for an auto section and didnt see one, just the headlight part, sorry for my confusion. Ill look for a place to post elsewhere!

Yes there are some already produced, like these:

11" AVS RED L.E.D. TAIL LIGHT KIT WITH CLEAR LENSES

However, what I’m trying to do is a bit different. Mine will not be able to stay straight like the ones i linked. The only difference between whats linked and what I’m trying to do is

1.whats linked and readily available wont bend around what I’m going to be out to bend around.
2. They dont currently work in sequence right out of the box. They would also need to be customized to do so.

Also the red to white issue, isn’t really much of one. I assumed i could just run the clear LEDs to the reverse switch, and all of the red work together. So ultimately i was expecting to have 4 runs of LEDs on both sides. Two runs would be red, and two clear.

[AK-Adventurist]

Fact; without a reflective surface, they will be 100% illegal in the United States, as of the late 1960s. Just because its done a lot doesn’t mean its legal. I’ve built enough custom trucks to know, and I know people who have been ticketed, and impounded for “simple” lighting violations.

Also in many states, LEDs are illegal for taillight use at all, even as replacement bulb units in factory stock vehicles. And that Mustang is illegal anywhere that requires red taillight lenses(a great many places)regardless of LED or reflective.

Otherwise;
sounds to me like you might want to look at the light “ropes” basically that they sell for the angel eyes look, usually in headlights, but I’ve seen it in red, and amber for turn signal. Extremely flexible for contoured install. Sequenceing, I’m not sure about.

Also look at the long strip lights they make to go on trucks in the gap between the tailgate and bumper. Some of those sequence, and while most are at least about 4’ long, since they seem to be just strip light leds, if wire in sequence, you might just clip them shorter. And they pretty are flexible, but only in one direction, not rope like… Cheap enough to try anyway. I have 4 of thosr stacked together, for a 2" high by 7ft wall off taillight on a custom flatbed. A litle wire clipping and only the outer 2 are brake lights, but only inner 2 light for backups, breaks up the wall of light, better contrast taillights vs. brakes, etc.

[jdeez974]

I’m sorry but this “fact” of yours, is false.

100% of vehicles produced do not have reflective surfaces as yall are claiming. The only reflective part of the taillights are within the housing, not visible unless you have altezza style tail lights. Otherwise, they all have chrome reflective surfaces, covered with either white or red plastic housings. Regardless of what state you are in, if your lights on the rear of your vehicle light up as they should, they HAVE to show as red, amber, or white. Depending on what’s taking place. If your driving and your lights are on, red. If your breaking, red. If your turning, red or amber. If your going on reverse, white.

None of your housing has to be that same color. AS. LONG. AS. THEY. SHINE. RED. Have been there, with cops, multiple times. My first truck, 91 s10 square body, had the all white tail light housings frlm APC. Every week i was pulled over bc i would go get new red bulbs, or red covers for my bulbs and they would turn pink then white within days of purchase. Until i bought clear LEDs that shined red. Never again did i get pulled over for my tail lights for the other like 6 years that i owned that truck.

The mustang i showed, 100% legal, because when they turn their signal on. Red lights. When they hit their brakes, red lights. It’s the exact same as having your clear bulb, inside a red housed tail light. 100% legal.

Once again, previous guy mentioned LED ropes. Those are not what I’m looking for. I posted a link directly to what I’m looking for, which is a very basic version of what I’m trying to build. Your thinking i want altezza style tail lights with halo rings. No where in my post did i mention anything of the sort. Then your discussion the “line of fire” that people put under their tailgate. While this is closer than the halos your thinking of… both aren’t it.

I don’t need help choosing a style of LED.

I have that figured out.

What I’m trying to figure out, and am asking for help with. Is again this:

From my original post
1.these tail lights will in a straight line, and I’m thinking about 15" in length. How many LEDs should I use for this? Like I’m not sure how close they should be measurement wise from one LED to the next.
2.Is there/should I use a PCB board to set all of this up on and have my car’s wiring run to it and that board do basically all the work?
3.What all am I going to need other than a)LEDs of both colors b)resistors c)soldering equipment?

Basically, in a nut shell.
A. Should i use 3mm or 5mm LEDs?
B. I need a run of them in an almost straight line of about 15 inches, how many should i buy? Is there a rule for how close they can be to each other?
C. Do i need to buy a PCB board to have them ran to for switching on/off? Also same question for sequential function?
D. For 15" of LEDs how many/how big resistors do i need when running off a 12v system?

These are my questions, your legality mess os for the birds and inaccurate (100% so in my state, and the 10 states I frequent most. So continuing to try and explain that I’m wrong isn’t going to do Anthony but have you proven that you are as such. Here is another photo of actual 100% factory produced tail lights that show you that there is zero reflective on the outside of the lense, and ill replace the link for the ones I’m saying are basic that you clearly missed prior.

[AK-Adventurist]

Nevermind

[jdeez974]

I mean, your excused. Just stating that i posted my questions ( the 1-3 part) in the original post.

And so far have only received recommendations on ebay premade items to use, when what I’m asking for is clearly going to have to be custom as stated in op.

Oh and of course, the half ass lecture from u and ur senior DOT officer, that still doesn’t hold water lol. And ya you said “without a reflective surface” and the refereneced back to the 60s about the reflection. That’s wrong, just like todays lights, those back then still required something internal to bounce the light off of it. Even though that’s all that has ever been required, a perfectly clean, brand new pair of tail lights (like the mustang had shown) is 100% legal due to the FACT that if they shined red when legally needing to. They do so.

[L4M4]

I wouldn’t use 5mm LEDs, SMD is the way to go. 2835 to be precise.
You would have to design and have produce an MCPCB with the red and white LEDs on it, for the red ones it would be good to have like 4 to 6 them in series, depending how fluid you want the turn signals to be.
Single red LED on 13.xV is bound to have a much more complicated circuit because otherwise you will burn a ton of energy.

Maybe two rows of red could be a solution. One with all the LEDs in packs of 6 with a simple resistor, one with single LED + resistor for the turn signal.

And please make sure that the tail light and turn signal are visible from the side. Very important for safety.
Best to make a daughter board and mount it in a 90° angle to the other one.

[Lightbringer]

Obligatory disclaimer…

Just because someone doesn’t get pulled over by cops doesn’t mean what they’re doing is legal. Here in NYC, we had that fad with those retards slinging those then-ubiquitous light-bars in front of their grilles blinding every one in sight, and rarely getting pulled over. Same with other retards riding with their brights on. And those things are more conspicuous by presence than by absence.

Thank B’harni (pbuh!) that that fad died out, probably as those retarded light-bars fried themselves and weren’t replaced.

That said, taillights need to be bright enough to be seen in direct sunlight. I switched from my 3057s to I think 3357s (40W vs 30W) for better brightness, then to red LEDs (might’ve been JDM Astar, forgot), which after replacing one side and comparing, was at least as bright off-axis and even brighter on-axis than the hotwire bulb it replaced. Have had them in there for years, no issues other than the fastblink, which I actually like and kept.

My other car, did the same but with amber lights to replace the 3156NA or whatever they were. Also brighter than stock hotwire bulbs, but wired in small resistors just big enough to fool the 'puter to not throw bulb-out errors. So 50Ω worked, but used 33Ω or so just for a little margin. Ie, NOT the scorching-hot 6Ω resistors everyone and his grandmother use.

Stock housings, no modifications except for the spliced-in resistors in the latter. And yeah, they all have the retroreflective red areas on the housings.

Point being, I f’ed around with lighting and did it to avoid anything that would invite der Polizei to come sniffing around.

Custom lighting strips… Okay, if you’re determined, then go crazy.

5mm/3mm even if tightly stacked won’t have nearly the intensity to show up in direct sunlight. And you really can’t push them pretty much anything beyond their rated specs without having them start blinking/flickering. I did that with white interior lights at only 17mA per, and now they flicker like I’m in a f’n disco. Don’t forget that load-dump from the alternator can kick up the voltage from 14V to 30V-35V spikes, or more.

So you’re going to need active regulation to at least eat those high-voltage spikes. Also, you can probably forget light-strips or even those 4-pin “high-flux” LEDs. Fine when packed into a CHMSL, suck in actual taillights. But maybe… MAYBE… you can pack 'em end-to-end and get decent enough intensity.

What to do about white? No idea. Dunno any “RW” chips, and RGBW chips on those light-strips are spaced way way way too far apart to be any good. You’d need a custom strip to, again, pack 'em end-to-end for them to be bright enough and to not look like a dotted-line.

There are “smart chips” which can be addressed individually on strips. If you’ve ever seen those “icicle lights” for Christmas, you have an idea of a mainstream use for them. But you’ll need a smart controller (and have to program it yourself) to do the whole turn-signal thing.

Wellp, that’s about it for now. Tired, going to sleep…