After posting my car for sale in the mall, a TON of people have been asking me about my LED tails. I don't remember any specifics, like measurments, or resistance on the circuits, it was a long time ago I did this, sorry. Well this is how you make them...

First you tear the lights apart, just release the tabs around the light. You have to be VERY carefull not to brake the tabs, the lens' are VERY expensive. Once the light is apart, you have to make a template out of cardboard, like so...



I got my LED's from www.Besthongkong.com IT took a while to get here, but they are good quality. they are 10mm LED's BTW.

After you have your template you have to get yourself some thin ABS plastic, or the equvelent. Drill a TON of holes, looks something like this when the LED's are in place...



Wire them all up, glue them in place, and make sure you use the correct resistors. I can't tell you what resistor to use, because there are differnt LED's out there that use different volteges, so you will have to know some basic electronics here. Cram it back into the lens, check for fitment...



Put the entire assembly back together and it should look something liek this...



Now for the easy part, the LED modulator. LED's can't dim, so you have to make them blink REALLY fast, so fast the human eye can't see it, it sees it as dimming. Here are the schematics of it. These are correct to a point, I didn't draw in the diodes you will need for the incomming power, I just put those befor this circuit. It is nice having a girlfriend whos father is an electrical engineer, he literealy drew this up on a napkin when we where out for dinner, then he madeit nice on a computer so I could read it.


You only need to make one of these modulators, because the brake lights are the only ones that will dim, the turn signals will run straight off the socket in the car.

Here are a few finished pics of it on the car, it is so hard to get a clear night shot...

and with the 4 ways on so you can see the top part


Sorry for the quick and dirty version, but I did this so long ago I forgot most of the specifics.

And no I will not make more sets, it is a real pain in the @ss, sorry.

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Those lights look really good and nice writeup. A+

Very cool mod and very nice writeup

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www.fierodomain.com
Your guide to the Online Fiero Community, always under construction

Very awesome. I was about to PM you about how you made these. Thanks man

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NIFE

98 Grand Prix GTP Black
88GT Silver- bone stock (Sold)
87GT Blue- 3.4 roller cam, coilovers, 88 cradle swap, many other mods
www.comcast.net/~mark3340/default.htm

Do you remember if they were the pure white LED's or the white LED's?

Very nice right up by the way. Good job.

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Awesome. That is exactly what I wanted to know. I have been trying to figure out how to make LED tails for a few months now but was unable to actually find any info. Guess I have some parts to buy now.

I guess now I just have to figure out what that schematic means... Also, I can barely read what the schematic says...

[This message has been edited by el_roy1985 (edited 11-10-2006).]

quote Originally posted by 87FieroGT: Do you remember if they were the pure white LED's or the white LED's? Very nice right up by the way. Good job.

\

They are not white at all, they are the red, and amber LED's

Is there any way that you could possibly post a bigger picture of the scematic diagram?? Even if it is over 100k, that would work. I really can't see what the other one says. If you want to email it instead, that would work to. Thanks again, Mark

quote Originally posted by Dough19: Is there any way that you could possibly post a bigger picture of the scematic diagram?? Even if it is over 100k, that would work. I really can't see what the other one says. If you want to email it instead, that would work to. Thanks again, Mark

Try this one
http://img237.imageshack.us/img237/1043/ledmodulatorqb9.jpg

This is the largest I can get it, hope you can read it.

Nice job. +'s to you.

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Ernie

1988 Silver GT
One owner 47000 miles.
Soon to be a 3.4 DOHC powered.

quote Originally posted by Golden86: Try this one http://img237.imageshack.us/img237/1043/ledmodulatorqb9.jpg This is the largest I can get it, hope you can read it.

Much better size. Now I can actually read it.

ok, who will make these for me? and how much cash do you wan't, I can send the tailights to ya. someone interested in spending some time to build these for me, PM me I am serious. cash is not a issue unless its very unreasonable.

Hey guys,

I've started modifying a spare set of notchback tails for LEDs. I haven't bought my LEDs yet but I've pretty well figured out how they'll work. Here are a couple of good sites for info if you want to tackle this:

Wikipedia Site on LEDs
Excellent site for figuring out resistor values
Good deals on LEDs

I should be ordering the rest of the parts I need this week so should have some in process pictures soon.

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http://www.raceme.cc/helmet/

Um... I hate to burst your bubble but LEDs can dim just fine. All it takes is a larger value current limiting resistor.

That said, I've been planning a mod like this for years for my Formula. One of the questions I haven't answered yet is to dim, or modulate. You, sir, have just made the modulation option so very much easier as I won't have to design my own circuit if I go that route. : D

Another option I'm currently researching (as much as I ever reseasrch anything) is using indirect illumination for the running lights. Think FoMoCo Thunderbird/cougar of the late 90's but add direct illuminating brake lighting deeper in the lenses. I suspect I can get the job done using the backs of the original red portions of the lenses. Time will tell, I've already got a spare set to play with but need to make the car mechanically sound first. } ; ]

Red 5spd Formula (and Yellow, it needs to be Yellow!)
Trot, the always planning never doing, fox... { : (

quote Originally posted by TrotFox: Um... I hate to burst your bubble but LEDs can dim just fine. All it takes is a larger value current limiting resistor.

I did not know that, I only thought they could dim to a point, and then the current will become to low, and they will just shut off.

I don't know that much about electronics, just a little more than the average person. It's nice to know an electrical engineer

[This message has been edited by Golden86 (edited 11-13-2006).]

LED brightness is a function of power across the junction, just like it is for power across the filament of an incandescent bulb. There's just less current and (usually) voltage involved. However, the PWM circuit you used likely wastes less power than simply adding a resistor in series and, for those of us with fast retinas) makes the car more noticeable. : ] If you ever use an LED flashlight, the batteries can be used all the way down until you can only barely see the LED illuminate. : ]

BTW, how many LEDs did you run in sequence for each circuit? My experimental third light had sets of 6... 105 5mm LEDs total. = O

Red 5spd Formula
Trot, the wire-headed, fox... } ; ]

quote Originally posted by TrotFox: LED brightness is a function of power across the junction, just like it is for power across the filament of an incandescent bulb. There's just less current and (usually) voltage involved. However, the PWM circuit you used likely wastes less power than simply adding a resistor in series and, for those of us with fast retinas) makes the car more noticeable. : ] If you ever use an LED flashlight, the batteries can be used all the way down until you can only barely see the LED illuminate. : ] BTW, how many LEDs did you run in sequence for each circuit? My experimental third light had sets of 6... 105 5mm LEDs total. = O Red 5spd Formula Trot, the wire-headed, fox... } ; ]

If I remember corectly, I think I used 4 10mm LED's in series with a 220 ohm resistor.

Quick question...

What do you get when you hot-glue 105 5mm LEDs into a third brake light?

A Big Mess!





Still not as bright as the stock lights but that may be due to my window tinting. I should try compairing the old and new some day. This unit was bought and moded so that I still have the original in case I didn't like this one. It's been running like this for about 5 years though with only one set having stopped working. When I pulled it to repair it tonight I found 3 broken joints, 2 were still conducting but would break contact if the lense was flexed. : ] Next time I use 10mm LEDs and a template to keep everything lined up!

Trot, the learning, fox...

quote Originally posted by TrotFox: Um... I hate to burst your bubble but LEDs can dim just fine. All it takes is a larger value current limiting resistor.

Yes.. but that method will also increase heat generated and shorten the life of the LED... The method that Golden used will be easier on the LED and allow more variation on brightness, its more complex but it looks damn nice.

DON'T SELL THE CAR GOLDEN86!!!

quote Originally posted by carbon: What is the hand drawn line from the Taillight(+) with the LED and resistor to the output of the circuit for? And what diodes for the incoming power? Like regulation or what?

That is so you know if the output is working. Since the output provides the ground for the light circuit the LED would light to let you know the board is working. Otherwise if you installed it and hit the lights or brakes and it did nothing you would not know if you where missing power to the tail led's or the board was not working or connected wrong. Just makes it a quick way to know which way to look for a problem. It also provides a bias path for the Mosfet if you did not have any tails connected to test the board.


The 15V zenor diode would clamp (limit) the voltage to the chip to 15V. Just protection for spikes since the voltage should not really exceed 14.7 volts if your regulator is working correctly.

[This message has been edited by Dodgerunner (edited 11-18-2006).]

Nice mod!

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Visit my website!
David
2 Corinthians 5: 17
1987 Pontiac Fiero GT, 5 Speed
2005 Pontiac Grand Am SE, 3400 V6

quote Originally posted by Dodgerunner: That is so you know if the output is working. Since the output provides the ground for the light circuit the LED would light to let you know the board is working. Otherwise if you installed it and hit the lights or brakes and it did nothing you would not know if you where missing power to the tail led's or the board was not working or connected wrong. Just makes it a quick way to know which way to look for a problem. It also provides a bias path for the Mosfet if you did not have any tails connected to test the board. The 15V zenor diode would clamp (limit) the voltage to the chip to 15V. Just protection for spikes since the voltage should not really exceed 14.7 volts if your regulator is working correctly.

Very good! Thank you sir. Its funny how you can look at something completely bass ackwards and then some says what it really is and you have to slap yourself

[This message has been edited by carbon (edited 11-18-2006).]

quote Originally posted by carbon: What is the hand drawn line from the Taillight(+) with the LED and resistor to the output of the circuit for? And what diodes for the incoming power? Like regulation or what?

That hand drwn line is for a status LED, you don't need it, but it lets you know if its getting power, and how dim they will be.

and the diods are there to keep the system from bakfeding into your car. I had the problem when ever I pressed the brake pedel, the parking lights would come, a simple diode solved that.

quote Originally posted by carbon: Yes.. but that method will also increase heat generated and shorten the life of the LED... The method that Golden used will be easier on the LED and allow more variation on brightness, its more complex but it looks damn nice.

How do you figure more heat is generated in the LED with lower current due to a larger limiting resistor? This isn't an induction motor we're talking about. Heat generated at the resistor would also be lower or about the same due to less current flow overall. All the research I've done indicated a linear arrangement for current flow and heat generated at the junction. Do you have other info? If so I'd really like to see it!

Red 5spd Formula
Trot, the certain, fox...

if your gonna go that far into it, couldnt you set it up so it has 3 segments vertically that sequence from inside to outside like a johnson counter would? or something like the mercury cougars from way back when? would take a little bit more circuitry tho.....


or maybe even a ring counter would look cool.

quote Originally posted by TrotFox: How do you figure more heat is generated in the LED with lower current due to a larger limiting resistor? This isn't an induction motor we're talking about. Heat generated at the resistor would also be lower or about the same due to less current flow overall. All the research I've done indicated a linear arrangement for current flow and heat generated at the junction. Do you have other info? If so I'd really like to see it! Red 5spd Formula Trot, the certain, fox...

Bah... I thought you were talking about reducing the size of the resistor to make it brighter... You are obviously correct in your theory Golden's circuit will allow for a lower range of intensity... beyond the shut off point. So if the LEDs are too bright at their turn on current, one will need a circuit like mentioned above.

[This message has been edited by carbon (edited 11-24-2006).]