sick!! I got to do this to my someday.

 

Kickass!

 

Looks great!

I wonder if I can get British Racing Green LEDs....

C ya,
Dutch

 

http://youtu.be/r0EXJR1oa4U

 

I have no idea what i did wrong i did everything according to this tutorial but my led started smoking right when i connected it :(

 

Every electronic part contains magic smoke inside it that makes it work.

My guess is that your LED didn't have a built-in resistor to let it run on 12V and the resulting over-current situation let out the magic smoke.

LEDs drop anywhere from 1.5V to 5V, depending on their color. Shorter wavelengths (blue end of rainbow) drop more, longer wavelengths (red end of rainbow) drop less. I've even seen infrared LEDs that drop as little as 1.2V. So, there needs to be a resistor in line to drop the remaining voltage and limit the current on the LED to less than 20mA.

Assuming a blue LED (everyone seems to be in love with those lately), that means you need 8.6V to be handled by the resistor (5V + 8.6V = 13.6V, which is about what your car sees when charging). This means you need a 470 Ohm 1 Watt resistor, which limits current to 18mA (8.6V / .02A = 430 Ohms; nearest higher standard value, since we want to be *less than* 20mA: 470 Ohms, so 8.6V / 470 Ohms = 18.29mA), wired in series with your LED to keep the magic smoke inside. You really only need a half watt, but I prefer overkill design when putting a circuit together in a hard-to-reach spot....

HTH!

C ya,
Dutch

 

Yep, you probably didn't have LEDs that were set up to handle the 12v.
I got my leds from oznium.com they have the 12v units ready to go.