Changing colors in you LED's for your ABL

[sternfan69]

Thanks for the reply. I was kinda thinking a list of all possible leds you can change in the car like steering wheel, gauges and wherever else or are they all the same size?

[sternfan69]

All the leds tidewater said.

[copper3000]

Originally Posted by TidewaterShark

I am just starting with this mod. doors first. want to change everything blue. window switches in the door. On the steering wheel, speedo and tack, the 4 gauges in the console. the radio if it can be done???

That'll look awesome!

[2SSRS@Gen5diy]

Originally Posted by sternfan69

All the leds tidewater said.

No there not, there all kinds of size, there are DIY for all the rest by a member other then me.

[CaryE1]

Originally Posted by TidewaterShark

I am just starting with this mod. doors first. want to change everything blue. window switches in the door. On the steering wheel, speedo and tack, the 4 gauges in the console. the radio if it can be done???

Tidewater, it can be done - most of mine are now red, including gauges, radio display window & dash controls. There are some other DIYs which discuss how to go about changing the gauges, steering wheels & radios. FYI there are several different sizes/types of LEDs you'll need, and if you want everything blue, you'll end up changing close to a couple hundred if you want to get them all done.

[Skexies]

Well, I just saw this post referenced in another post... so I will throw some shoulder behind it, as I see people wondering "what resistor do I need?". If it is redundant, so be it.

I'll start out basic and then get a little more complicated, if anyone doesn't fall asleep.

You run resistors in-line with an LED to restrict current flow across the LED. LEDs are manufactured for an expected voltage & current. Too much and it'll burn out.


Quick on resistors:
Think of it like a garden hose, the resistor is used to kink part of the water coming out the other end.

The amount of kink is measured in OHMs for resistors, 1 being low and 10,000 being higher (or a lot tighter clamp down).

Color codes on the side of a resistor tell you the ohm value (number) and some other information like how precise it is. You can find color code translators on the net if you can't find the pack your resistors came in.

Resistors don't have any direction, they work the same backwards and forwards.

What is important is that you know the resistance value.


Quick on LEDs:
LEDs are not light bulbs. Lightbulbs have resistance. LEDs have (basically) no resistance to them, so they will try to arc just like a wrench across battery terminals. (aka, bad for LED and maybe bad for the source if enough current zaps before the LED burns out.)

So, LEDs have to have SOME resistance to regulate power flowing. A resistor.

There are formulas (hang on, don't panic yet) to figure out what the right resistor is for a specific LED.

LEDs have design expectations and tolerances (just like some motors handle a 40 shot of NOS and some a several hundred shot of NOS)

What you need to know is that each LED part # has different expectations and so each part has a different resistor needed. (Frankly, they can vary by size, color, and even different production runs from the same manufacturer) Some folks already calculate this for you (maybe) and sell pre-packaged LEDs with resistors attached.

You can look at manufacture's sites or the information on the packages to get something like the following:

Wavelength: 490nm
Luminous Intensity: 4000mcd typ. @ 20mA
Max Forward Current: 30mA
Pulse Current: 100mA for <= 10ms, duty <= 1/10
Forward Voltage: 3.5V typ @ 20mA
Max Reverse Voltage: 5V
Power Dissipation: 70mW
Operating Temp: -30 to +85 C
Soldering Temp: 260 C for 3 secs
Max Reverse Current: 50uA @ 5V



I'll get into this later but the really important piece you need is this:
Forward Voltage: 3.5V typ @ 20mA



NOTE: LEDs are not designed to run at redline all the time. They have to get rid of heat too.


Ok, let's talk about your power source:
Your car's electrical system produces a wide range of voltage, from 10 to 15v but normally around 14 when the alternator is running. This is important to know, because LEDs are horribly sensitive to voltage changes. In fact, it is exponentially so and not linear.

(Exponentially: 1 in makes 1 out, 2 in makes 4 out, 3 in makes 20 out, 4 in makes 1000 out )

So what you need to know is that 14 volts applied to an LED is FAR FAR more power than 10 volts. So you will want to expect 14 or 15 volts when calculating the proper resistor, NOT 12.


Gotta know the voltage drop of your particular LED:
Shortcut: I'm not going to get into details, but they use different materials to make different colors. assuming clear plastic LED and no colored plastic... red orange, green or yellow probably have a voltage drop of 1.9-2.1volts. Violet, blue to green or white are probably a voltage drop of 3.1-3.5volts

I'm just throwing those out there, vs. talk about how to measure voltage drop (most accurate) for your batch of each LED part#s or determining if you have one made with AlGaInP or InGaN, etc. Google if you really want to know.

Just know:
Red, orange, yellow, green LED, probably 1.9-2.1volts
Violet, blue to green or white are probably a voltage drop of 3.1-3.5volts


Finally, if you want to run more than ONE led... you have to know how you want to wire them (series or parallel).


OK!!! Ready? Armed with that information:
Let someone else do the math for ya.
http://www.hebeiltd.com.cn/?p=zz.led...tor.calculator

So in our example data I put up there, with a single LED (Forward Voltage: 3.5v @ 20mA), expecting 14.7volts in, guessing 3.3 volt drop because that LED is Turquoise / Cyan...

Data comes back out:
I need a 570 ohm resistor... BUT cheap resistors are like shotguns and not sniper rifles... they can vary 10% sometimes... so a 10% margin of error value (nicely calculated for us) give us 680 ohms and it should be able to handle 1/4 watt but 1/3watt is safer (also calculated).

So my Aqua colored LED will probably need a 680 ohm 1/3 watt resistor to go with it before I plug it into the ABL.

Hello Radio Shack:
http://www.radioshack.com/product/in...ductId=2062322
680 ohm 1/2 watt. [the only problem with larger watt resistors is size, if you can fit it in place... it won't impact the function of the circuit]



So there you have it.... that is how you get the CORRECT resistor value to go with your LED.


Finally, you should know that over driving the LED doesn't really give more light. It is not like a light bulb. You just basically burn it out.

Remember those LED specs?
(Luminous Intensity: 4000mcd typ. @ 20mA)
LEDs will have how bright they are, designed into them.

What color is it?
Remember those LED specs?
Wavelength: 490nm



Wavelength will give you the color of the light at the DESIGNED voltage & current. (yup, it will change sometimes if you underdrive, etc.)


One final piece about LED colors:
RGB multicolor LEDS will not produce pure spectrum light. They can't. You will probably get a blend of three pulsed colors and some odd resulting shadows. It will be MUCH more apparent in photos and videos as the colors won't seem correct.


Not that they are bad... just know they are not pure like a single color LED.

Ok, I'm done... Hope that helps someone...

[Skexies]

Ok.... and now my super short version:
What resistor to use to get 20ma of current??

http://www.ledsupply.com/04006-020.php

DynaOhm 4006 is an active device that functions like a dynamic resistor. As the voltage changes in the car's supply, it adjusts resistance to keep the LED driven at 20ma. (well 20,25 or 30ma depending on which model)

They are about 2.63 a piece. No guess work and as your voltage shifts from the charging system... it adjusts.

With 12v of input... you could use one DynaOhm with 3 LEDs in series behind it. Back to that voltage drop thing.

Don't expect dimming action if it is done by voltage drop... I expect this will just try to correct.

[OmniCamaro]

subscribed for later!

[RayTheRat]

Originally Posted by Skexies

Ok.... and now my super short version:
What resistor to use to get 20ma of current??

http://www.ledsupply.com/04006-020.php

DynaOhm 4006 is an active device that functions like a dynamic resistor. As the voltage changes in the car's supply, it adjusts resistance to keep the LED driven at 20ma. (well 20,25 or 30ma depending on which model)

They are about 2.63 a piece. No guess work and as your voltage shifts from the charging system... it adjusts.

With 12v of input... you could use one DynaOhm with 3 LEDs in series behind it. Back to that voltage drop thing.

Don't expect dimming action if it is done by voltage drop... I expect this will just try to correct.

Its behavior seems to be very similar to Zener diodes which have been around for years. They're voltage-sensitive and have a fixed "breakdown point" and it appears that this might be current-sensitive rather than voltage-sensitive.

I've never worked with these, but they might be pretty good for situations where a fixed output current level (as opposed to a fixed output voltage level) is required. It might be interesting to see if a Zener would work as well for creating a steady current (as per Ohm's law; current is a function of resistance and voltage).

If I ever get caught up on projects that are already half-done, I might try experimenting with one or more of these in series with a resistor and an LED.

Here's a link to a discussion about 'em:
http://www.candlepowerforums.com/vb/...esistance-Data

[G-Oil Guy]

So is this a simple swap out or is there soldering involved?

[The Stig]

Originally Posted by G-Oil Guy

So is this a simple swap out or is there soldering involved?

I believe a tiny bit of soldering is involved, but could be wrong.

[emason5]

For anyone who wanted to do a colorshifting ABL DIY: http://www.oznium.com/rgb-color-changing-led

it might take some modding to get it to fit in the led holder as ive heard, but itd be cool.
Id do it, but id prefer to have some kind of remote.(rather than it shifting on it own)

maybe wired it into my existing rgb floorwell lightint?

any thoughts or recommendations?

[sjmautoprod]

The constant-current drivers should work fine with standard, PWM dimming. No resistors needed with those.

[emason5]

Originally Posted by sjmautoprod

The constant-current drivers should work fine with standard, PWM dimming. No resistors needed with those.

Why would no resistor be needed? They're on the stock one aren't they?
I'm slightly confused what you're saying, clarify please!