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hey guys. no one seem to reply to my questions.
anyways. can someone tell me what kind of leds i should get so i can have them light up when i turn on my parking lights? i need white ones. also i need to know what kind of resistors i need. thanks guys...

 
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go to radio shack... probably should get the high intensity ones (or something like that).

as for resistors, it depends on the LED. they come with a rated voltage and max current on them (i think the high light ones are 3.7V. DO NOT EXCEED MAX CURRENT or LED will blow. However, how much current it has really has no effect on how it lights up. Here is an example of figuring a resistor.

12V battery, .7V rated LED. LED's oppose the battery's voltage, so the total drop (battery - LED) equals 11.3V. max current is 20 mA. Voltage divided by max current = 565ohms. DO NOT go smaller than this. LED's have a minimum current need, but it's usually pretty low (1-3 mA). Try 1k ohm here for safety.

if you hook them one after another, add their voltages together. it is easy to know if you connected the right ends because they just won't work if you don't. Not a bad idea to test them and mark the positive side first. Post again if you have any other tech questions,hope this helps you out some.

 
Rep Power: 362

this is what i want to do
so im going to need (4) 3.7V and how many 1k ohm resistors will i need?
and what kind of wires should i use?
thanks

 
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OK. Go to Led's and order whatever color u want.
U need no resistor. if they are 4v LED's wire three of them in series for a 12v total.
If they are 3v then do 4 in series. Get it? It's not that hard once u try.
U can wire as many as u want cuz they draw very little current.
If u want you can patch them into the brake light wire in the trunk.
Refer to the wiring diagram to find which one to patch to.
Hope this helped! BTW I order from Super Bright LED's.com and they have very good service.

 
Rep Power: 330

notice that guy just used radio shack for his. i bought a 3.7V superbright blue one for like 3-4 bucks, pretty nice color.

for 4 3.7V leds, connect 2 sets in parallel (so split the wire in 2) to the positive end wire. each set is 2 3.7V leds and 1 resisitor (at least 250 ohm in this case, but 1k will work too). it is correct that these draw minimal current, but they do need some or no turn on. and no resistor can give you infinite current thus blowing the LED's (see first response).

oh yeah, any wire will work (no sig. current). show us pics of how it turns out too.

 
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do note however, that with white LEDs their light output coloration does (in most cases) vary slightly on the input voltage. i believe that if less voltage is supplied the LED seems to be more yellow in color, and if more voltage is supplied the LED appears more blueish in color. so, if the LED seems too much like one of those colors, and not a nice white color try varying the resistors a bit to get the optimal voltage.

 
Rep Power: 330

so maybe best choice... get a variable resistor, see what you like. wire the led's in parallel after the resistor (so you only need to buy one and so you can set all 4 the same way) and have fun.