LED resistor type

If you want to replace your brake lights with LED lights, they make cluster bulbs that come preloaded with LEDs and they fit into your old light socket, works just like a regular bulb only brighter and faster.  Find them at www.cardomain.com or any local auto accessories store.  Hope this helps.

--mindctrl

Do you know the specs of the LEDs? You will need to know the forward voltage around 1.7V for red usually. Then determine how many you will have in series, find the total voltage drop from all the LEDs and the find the difference of that volatage from the supply, resistor will dictate the current (I = V/R)

Sorry if this sounds vauge but I know this has been covered many times in these forums...

if you have 8 in series with 1.7V each it will be 8 * 1.7 = 13.6, so it really shouldnt be done since the supply is only 12. Lets say you use 6 instead...

6 * 1.7 = 10.2 V

so the voltage across the resistor is going to be 12 - 10.2 = 1.8V

I will assume you want 20mA through the LEDs (common value)

R = V / I

R = 1.8V / 20mA = 90 ohms, you would use a resistor close to 90 ohms

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now lets say you hook the other 2 up alone (ideally I would use 4 and 4)

2 * 1.7V = 3.4V

therefore the voltage across the resistor is going to be 12V - 3.4V = 8.6V

so the resistor value you are going to need is... (assuming 20mA again)

R = V / I

... ahh you calculate it  what should it be assuming the perfect 12V source?