legacycentral bbs

lol. Typos don't bother me. It's blatant spelling mistakes particularly in main posts that drive me nuts

Thank you! I picked up the red LEDs today at Fry's... hopefully tonight I'll have the needles working as well.

jnorion wrote:Thank you! I picked up the red LEDs today at Fry's... hopefully tonight I'll have the needles working as well.

Holler at your shopping at Fry's. Saved me tonight, let me tell you.

Fuck fry's.

It's all about digi-key

I got next-day delivery and Im in CANADA.

Im super impressed.

It was a pain in the ass last night because the LEDs were too big and I didn't have a drill. I have to stick the LEDs directly in the plastic light guides. There's less space than I thought there would be.

I'll try again today with the proper tools.

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 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.

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.

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.

Splinter wrote:Fuck fry's.

Seriously though, you don't know how it saved me.

Still working on the final stages of the project it helped me save, but it helped me, nonetheless.

was it the motherboard?

LED's need amps IIRC. Wire them in series and try that.

Blah. I didn't want to have to do that. Oh well, I connected them with wire nuts for a reason.

jnorion wrote:Blah. I didn't want to have to do that. Oh well, I connected them with wire nuts for a reason.

Wiring them in series would be a lot easier than doing it in parallel....

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.

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.

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.

so did this ever get solved?! totally cool with the blue!!!!

I haven't had a chance to redo it yet but I'm basically certain that I just need to use the LEDs without resistors. You can see the needles light up, they're just very dim.

Awsome thread.

Thanks, I'll bring it in and show you when it's done.

did you ever get this finished?
can you find a link to an online store with the right leds to do this?
thanks

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.

eather im dumb or i dont see which leds you got on there site

http://www.superbrightleds.com/specs/bulb_specs.htm

Those gauges look sweet. Can we see current pics of it?

At the moment they look pretty much the same as the last picture, but I'll get a better shot of it that shows it fully installed.