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Trying to make custom LED tail lights for my Honda S2000. Answered

Hi all,
    Anyone have any good DIY for wiring up LEDs to a 12V system? I found LEDs on ebay with resistors already wired in but im wondering if I should hook them up in series or in parrallel?

Im sure 12V is enough to power them but how can I make sure they dont burn up?

Is there a way wire up the LEDs to keep them looking straight and in line w/o taking for ever and postioning them perfectly? Maybe some kind of board or plate?




The leds on ebay wired with a resistor are good for one off things -- but they are NOT very efficient. The led uses 2-4 volts, and the resistor burns off 8-10 volts. Not good.

Advisable: because your car voltage can vary from 11 to 14.5 volts, its a good idea to have a voltage regulator in there to give you nice steady power. 

After that, you want to run custom strands of leds based on their individual characteristics, then use a current limiting resistor to tie it all together.  Series leds drop voltage (1 led = 2 volts, 2 leds series = 4 volts, etc), parallel leds drop current (1 led = 20mA, 2 = 40mA).

As to how to mount them all the same orientation -- Use a drill press and a 5mm bit.  Firmly mount the led holder on 'something that will keep its orientation pointed 'upwards' such that the beam would be straight up, then just drill all the holes at whatever angle that jig sets up for the drill press.  They will all slide into the 5mm holes easily without any alignment.  For cars I recommend Straw Hat leds (nearly 180 degree beam) so it can be seen from all angles.

Thanks frollard, Do you /anyone know of a good website to get LEDs? I was looking at the ebay ones since they were cheap and already wired, but are they not efficient to where they are going to burn out. I would like these LEDs, since they are in my tail lights, to last a LOOONG time. When all said and done, I should be able to wire the reds to the reds on my cars wiring harness and the blacks to the blacks right? I will just nee to cut off the connector that plugs into the back of the bulb right?

Ebay is my favourite. superbrightleds.com is good too. Your 12v preassembled ones will work red to red black to black.

Go down to your local autostore. They sell led replacement bulbs for car. Or are you looking for some custom shape?

Well the LED bulbs that fit in the sockets dont look like what im going fo / yes a new design too