i bought 36 or so 3volt leds to use in part with my current tail lights, just to brighten up my lens, so the question i have is how to i wire them so they work with my car? i heard wiring they in series, 4 leds,at a time can some clear up my confusion please
http://led.linear1.org/led.wiz
You'll need info off the spec sheet, output as schematic or wiring diagram. Use 13.8 as the source voltage for brake. You'll need the forward voltage (if it gives a range, use the high side) and mA rating. Resistor position is backwards on that site. It needs to go on the positive side of the LED's
Curious though... 3v should be white/green/blue.... red should be 1.8-2v...
Edited 1 time(s). Last edited Tuesday, July 15, 2008 4:30 PM
i was told they were 3v, i bought them for a reputable electronics shop, .39cents a piece, they shine red because the shell is red?
the wizard said i need 1/4 watt resistor, i put in i plan on using 4 leds,....but my question is, i plan on using 4 leds wired series per set, and using a total of 4 sets, so do i put a resistor on each set or at the end, i only chose 4 leds, because 4x3volts= 12 volts
Solution 0: 4 x 4 array uses 16 LEDs exactly
+13.8V R = 100 ohms
R = 100 ohms
R = 100 ohms
R = 100 ohms
The wizard says: In solution 0:
each 100 ohm resistor dissipates 40 mW
the wizard thinks 1/4W resistors are fine for your application
together, all resistors dissipate 160 mW
together, the diodes dissipate 960 mW
total power dissipated by the array is 1120 mW
the array draws current of 80 mA from the source.
You will need 1 resistor for each string since it will be in a series/parallel setup.
Example (this is using 18 LED's at 2 volts)
Using the above example, you will run 3 branch wires from the source, each with a resistor, each with the LED series. All 3 strings will use a common ground.
As for the red lens, there are 2 common types of LED lenses. One has a clear lens, the color is (in my opinion) more crisp. This type is the one that I prefer. The other has a frosted lens (with a sub-variant, either color matched for quick identification, or clear frosted), probably the one you purchased. The light output is diffused slightly, but at times not enough to notice.
I'm not doubting what you were told at the shop. It could very well be a white LED with a red lens, making it 3v.
The more LED's in the string, the lower wattage resistor you will need.
However, 1/2w resistors will do just fine. As for the park, use 1k ohm 1/4w.
So, you will need 3 of these (just with 4 LED's instead of 6). The 100ohm side will all be wired to the brake/turn wire. The 1000ohm side will be wired to the park side. All 3 have a common ground...
Edited 2 time(s). Last edited Tuesday, July 15, 2008 5:38 PM
ok, im totally confused, so i can use the same leds for park and brake? because i thought they could only be used for one of the other, i that is tru i just want to use them for parking lights, so they stay on and bright at night, because im keeping my stock bulb in there, the purpose of the leds is just to fill bright up the lense to make it more visble at night, but if i can use them for both, great if not i plan on wiring 16-18 leds for parking lights....thanks for the all the help so far also
after re-reading your post i see what your talking about, but my brake/parking lights have 2 wires going to them thats it, the turn signal is a seperate lens and bulb,
Yes. You can use the same string for both. Its the same concept as the LED bulbs, just in loose form. When 12v+ is applied to the 100ohm side (the brake light wire) it will temporarily ignore the 1000ohm side.
1157 should have 3 wires... brake/park/ground, however the ground should be attached to the outer cylinder, brake and park are on the bottom where the 2 contacts are. 2nd gen Cavs integrated the turn into the brake system (which I know you don't have, but someone who has one may be reading this post, hense why I marked it as brake/turn)
ok im going to look at my wires again today, but if it is, parking/brake on 1 wire, how do i wire it up then? the bulb is originally a 2057, but 1157 work. ill look today and post a picture of it today when i get outa work around 5ish. I think having a visual might help me, and possibly help you tell me?
Ok, hope this clears some things up. Here is a pic of a standard 1157 socket (from my dad's motorcycle, but same nonetheless).
The 2 prongs in the socket itself are for the park and brake(/turn) positives. The ground wire is the little strap on the right of the socket. The outer metal cylinder of the bulb (as seen below... sorry this one is washed out) is the ground of the bulb. The 2 "nipples" are for the park/brake positive.
So, when you wire up the LED's you will want to tap into the two wires that lead to the contacts in the socket. Ground can be just about anywhere you can get a good ground (ie ring terminal on the stud that is for the tail housing since the stud passes through metal)
Now as for the LED action, the above schematic I put up can be best looked at in the following vid.... the quality isn't too great, had to get it to where it wasn't a pain for me to upload on 56k, but it explains the point. Also it may be a bit before it shows up since I just uploaded it.
I took 6 red LEDs on a test board and applied one 100ohm resistor and one 330 ohm resistor in series (total of 430 ohms resistance.... you might want to get something close to that in a single resistor, since it dims down quite a bit). The 330 is closest to the LED's and the 100 is farthest. I then applied 12v+ to the farthest edge from ground on the 100ohm. This simulates the state when the park light 12v+ is applied.
With that wire still hooked up, I then took a second wire from the 12v source and touched it to the 330 ohm on the farthest side from ground (in case I was applying over 12v, didn't want to pop the LED's). This simulates the state when the brake light 12v+ is applied
In the vid, you will be able to see that the LED's brighten and dim (mostly) as the second 12v+ is applied.
Electricity will take the path of least resistance, so it will ignore the full 430 and go with the 330 only, brightening the bulbs. Remove the second source from the 330 and it has no choice but to use the full resistance, dimming them.
thanks, alot, not being sarcastic, that did help alot, i plan on wiring only a few leds up, and actaully installing another 1157 bulb and socket assembly. On that note, i looked on my drivers side rear, brake/parking bulb assembly and there is 4 wires( blue,2brown, 1 black) where as on the pass. side there is only 3, any idea why theres 4 not 3, because im trying to wire in a second socket, and this is the only thing holding me up, pass side went together fine, and i read through a few repair manuals i have and no mention of it.
brown should be park, black should be ground, blue should be brake... it might be that one of the extra brown wires goes to either the plate lights or to the passenger side
