Changing my interior lighting color (no 56k)
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OK, so I finally finished getting everything set up. I took the gauge cluster apart to examine it. The light is channeled through clear plastic and into the gauge needles, like this:

I soldered some wire leads onto the LEDs and, drilled them into the plastic light channels to hold them in place, and then hot glued them. This way the red LEDs shine directly out at the needles, but don't shine onto the gauge faces which are supposed to stay blue. I also put a piece of electrical tape on the side to shield the gauge faces.
Here's what it looks like with the LEDs attached:

Then I ran the wire leads outside the gauge cluster box and around the back to join them all together, and crimped on some quick-release connectors so I could remove the cluster still.

So now I have a problem. I plugged it into the car to test it out, and it barely works. The needles visibly light up red while the rest stays blue, so I know that my design is good, but the LEDs are not getting enough power and so they are so dim you can barely see them. The box says they need 12v forward power, and they have a built-in resistor, so I wired them in parallel. I tapped into the backlighting wires on the gauge cluster harness, which I tested with the multimeter first and which gets a full 12v (when the dimmer is up all the way), and the blue lights which are attached to the same circuit light up the same as always so I know I'm not just overloading it.
How do I fix this? Do I need to wire them in series? Do I need to add some kind of amplifier or transformer or something? Help!

I soldered some wire leads onto the LEDs and, drilled them into the plastic light channels to hold them in place, and then hot glued them. This way the red LEDs shine directly out at the needles, but don't shine onto the gauge faces which are supposed to stay blue. I also put a piece of electrical tape on the side to shield the gauge faces.
Here's what it looks like with the LEDs attached:

Then I ran the wire leads outside the gauge cluster box and around the back to join them all together, and crimped on some quick-release connectors so I could remove the cluster still.

So now I have a problem. I plugged it into the car to test it out, and it barely works. The needles visibly light up red while the rest stays blue, so I know that my design is good, but the LEDs are not getting enough power and so they are so dim you can barely see them. The box says they need 12v forward power, and they have a built-in resistor, so I wired them in parallel. I tapped into the backlighting wires on the gauge cluster harness, which I tested with the multimeter first and which gets a full 12v (when the dimmer is up all the way), and the blue lights which are attached to the same circuit light up the same as always so I know I'm not just overloading it.
How do I fix this? Do I need to wire them in series? Do I need to add some kind of amplifier or transformer or something? Help!
~Joel
1991 Legacy LSi sedan | 1990 Legacy L wagon
1991 Legacy LSi sedan | 1990 Legacy L wagon
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I don't know if led's need amps or volts, but wiring them in parallel, you're going to have an amp drop.
That built in resistor could be killing you as well.
This is vikash's main area..he knows about this stuff.
That built in resistor could be killing you as well.
This is vikash's main area..he knows about this stuff.
1995 Polo Green Subaru SVX (189k miles - 08/2007-Present)Manarius wrote:The Neo-Cons would call me a defeatist. I'd call me a realist. I'm realistically saying that a snowball has better chances in the blazes of hell than democracy has in Iraq.
Yeah, that's what I couldn't remember either. I thought it was volts, but I really don't know. But I figured that parallel would be better specifically because of that built-in resistor.Manarius wrote:I don't know if led's need amps or volts, but wiring them in parallel, you're going to have an amp drop.
~Joel
1991 Legacy LSi sedan | 1990 Legacy L wagon
1991 Legacy LSi sedan | 1990 Legacy L wagon
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Wiring them in series would be a lot easier than doing it in parallel....jnorion wrote:Blah. I didn't want to have to do that. Oh well, I connected them with wire nuts for a reason.
1995 Polo Green Subaru SVX (189k miles - 08/2007-Present)Manarius wrote:The Neo-Cons would call me a defeatist. I'd call me a realist. I'm realistically saying that a snowball has better chances in the blazes of hell than democracy has in Iraq.
I just don't want to have to take the whole thing apart again. I had to stuff the wires in various little corners as it was, they'll be a pain to get out again. Not really a big deal, I'm just feeling lazy. And I was all excited at the idea of being done.
~Joel
1991 Legacy LSi sedan | 1990 Legacy L wagon
1991 Legacy LSi sedan | 1990 Legacy L wagon
umm.. I dunno WTF you guys are talking about, regarding LEDs needing amps or volts...
They need both.
But they'll draw as many amps as they need, the only limit is your charging system and the fuses.
If they've got built in resistors, you want to wire them in parallel, or they wont get enough voltage.
They need both.
But they'll draw as many amps as they need, the only limit is your charging system and the fuses.
If they've got built in resistors, you want to wire them in parallel, or they wont get enough voltage.
98 Steel Widebody RSTi-RA Superbeast
Theoretically, if you wire things in series the voltage drops for each thing you add, and if you wire them in parallel the amperage drops but the voltage stays the same. Incandescent light bulbs need volts, so if you wire them in series they get dimmer with each added bulb but if you wire them in parallel they stay bright. That's what we mean by "needing volts". I thought that LEDs worked the same, especially because of the resistors, as you said. Theoretically the whole car is wired in parallel... every light comes from the same charging system but is on an independent circuit.
I'm afraid I might have to go back and redo the whole thing using LEDs without resistors. At least they're only $.50 apiece.
I'm afraid I might have to go back and redo the whole thing using LEDs without resistors. At least they're only $.50 apiece.
~Joel
1991 Legacy LSi sedan | 1990 Legacy L wagon
1991 Legacy LSi sedan | 1990 Legacy L wagon
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http://www.superbrightleds.com has the bulb replacements. I ended up buying the red ones for the needles at a local shop.
I still haven't installed them though, I've been busy and lazy and then moved to a new house and lost all that shit in boxes for a long time, and now there's a slight possibility I might be getting a different Legacy to play with. But I'm getting ready to do it soon on one car or the other.
Oh, and I forgot an update a while back, I had the cluster out to work on it one night and the cat knocked it off the table and broke the temp gauge needle, so I had to replace the whole unit, which took a while.
I still haven't installed them though, I've been busy and lazy and then moved to a new house and lost all that shit in boxes for a long time, and now there's a slight possibility I might be getting a different Legacy to play with. But I'm getting ready to do it soon on one car or the other.
Oh, and I forgot an update a while back, I had the cluster out to work on it one night and the cat knocked it off the table and broke the temp gauge needle, so I had to replace the whole unit, which took a while.
~Joel
1991 Legacy LSi sedan | 1990 Legacy L wagon
1991 Legacy LSi sedan | 1990 Legacy L wagon
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http://www.superbrightleds.com/specs/bulb_specs.htm
Those gauges look sweet. Can we see current pics of it?
Those gauges look sweet. Can we see current pics of it?
90 L+ wgn