My LED's keep burning out., Why? Options

[richee3]

I have been using LED's in my gauge cluster for a little over 2 years now. The first set of LED's I had were cheap-o blue LED's from Ebay. After a while, the LED behind my fuel and engine temp gauge went out. But it didn't go all the way out. It started flashing on and off, between all the way off, all the way on, and about halfway in between. After a while, it settled down to being about halfway on, but it would still flash. I chalked that up to cheap LED's, and moved on to white LED's from v-leds.com. I got them put in last Christmas. Last Spring, same thing happens, in the same spot. The bulb behind the fuel/temp gauge starts flashing like it's burning out, but never goes all the way out. I moved it around, and no matter where I put it, it still flashed. So I replaced the bulb with a spare that I had, and a few weeks ago, it started doing the same thing. Now, the other LED's behind my speedo and tach, in my turn signal indicators, and in my key ring are all fine. Nothing ever happens to them. It's always the one behind the fuel/temp gauge, and it's always the bulb going out. I can move it anywhere and it still flashes. I find it hard to believe that it's just coincidence that 3 different LED's have gone bad, when they were all in the same spot. So... What's up with my LED's? Or, I guess, what's up with my gauge cluster that is making them burn out like that? I have a video of what they are doing, if anybody needs to see it.

Thanks in advance for any insight you guys have.

[lagos]

I had the same problem when I tried led's in my gauge cluster. Do you ever use the dimmer knob to turn them down?

[richee3]

Nah, not really. I do every once in a while, when it's really dark outside and having my gauges on makes it kinda hard to see. But for the most part, I leave them on as bright as they'll go. Dimming them does kinda smooth out the flashing, but they just settle down to being about half as bright as they should be. The other 2 I had go out before this one did eventually burn out altogether. I just find it odd that it's the same spot going out every time.

[SwissFerdi]

Don't LEDs take badly to dimming?

Or maybe the ones you bought just have STDs... Sorry people. Kind of a long back story to that.

This post has been edited by SwissFerdi: Nov 15, 2009 - 12:09 AM

[lagos]

Yeah, unlike normal bulbs, LED really need a constant voltage and shouldn't be dimmed.
Next time I install a set in mine, I plan on totally wiring out the dimmer switch so that they get consistent voltage at all times.

[richee3]

Hahaha Ferdi, I love getting inside jokes! Too bad nobody else will get that.

Thanks Art. I'll just order a new set of LED's and I won't touch the dimmer anymore.

[95st-celica]

i have had red led's in my guage cluster for a few years now and have never had a problem with them burning out...even when they are dimmed...but i never dim them either so that could be the case

[Bitter]

i'll bet the one thats failing is overheating. blinking led's usually mean overheating led's, atleast from my messing with them as a youth.

[SinisterSinner]

I have about 8 months with my custom made LED bulbs for the gauges, fuel, Hi beams, E brake and some others, and none have ever burnt and I'm always dimming the gauges, and still is like nothing, they work just fine, I spent like 3 months with a bad battery and I spent the whole 3 months with the gauges dimmed to the minimun to save as much electricity as possible to turn on the car lol, and my gauges still work like that 1st day.... and yea my reserve gas light is constantly on for some reason, but it has been like that form the first day.

[samir0189]

I have the same problem! On two different cars! the LED's blink then die. Oh well. back to incandescent bulbs...

[richee3]

^^ Exactly. I bought crappy LED's the first time around, so that was to be expected. Now I'm using v-led's, so I'm kinda surprised that this is happening. I've heard great things about LED's, like 95st-celica and SinisterSinner said, but I also hear people talking about their LED's doing the same thing ours are. I guess it's just hit-and-miss. The thing that makes me suspicious is that it's happening in the same spot every time. Like maybe that LED is getting inconsistent power or too much/not enough power. I suppose I should buy some stock in v-led's, because I'm NOT going back to incandescents. Lol.

[solidxsnake]

LEDs take fine to voltage changes, provided it's within their range. Are you overvolting them? Some LEDs have an operating range of 1.7-2.5v (generally Red) and some take up to 3-4v (generally Blue). If you run them too low, they won't light up, too much and they'll glow brighter than normal. Too high and you'll blow them.

I am currently putting together LED clusters for my dash. I bought 50 white LEDs ($.09 a piece) and am putting 4 LEDs to a cluster. I'm running them in series, 4 per cluster. That gives each LED 3 volts to work with, which is well within their safe operating range. I was planning on doing 5, running one of them in parallel. Worked for a bit, then I glued them together and put the volts back up to 12v, and the glue ended up breaking the series circuit, leading to all 12v flowing through the parallel'd LED and popping it in my face. Smelled awful, but looked cool

[richee3]

I'm running white LED's as bright as the dimmer in the car will go. I have no idea what voltage that is or what range my LED's are supposed to operate in. I never have read that far, which could be part of my problem. I just bought what looked good.

[lagos]

I'm running white LED's as bright as the dimmer in the car will go. I have no idea what voltage that is or what range my LED's are supposed to operate in. I never have read that far, which could be part of my problem. I just bought what looked good.

Try to bypass the dimmer all together. You could do this with a small paper clip in the harness plug.
Remember that the dimmer is a small potentiometer (like a vol knob in an old radio) and those are known to go bad over time. Maybe yours isn't sending out enough voltage to begin with.

[solidxsnake]

I'm not sure how the dimmer circuit works, but if it is directly linked to the +12v to all the lights, then there should be no problem if it's not "sending" enough voltage, too low volts won't kill LEDs (at least, I've never had problems from undervolting them). If, however, it's a part of a logic circuit and is screwing with the control of the circuit and overvolting them, there's a chance they're dying due to that.

I've seen the VLEDs before, actually placed an order for them, but when they didn't have them in stock, I rethought the robbery they were committing and canceled my order. Try grabbing a multimeter and checking the voltage across your dash board while running. Shouldn't be any higher than 12v. I'm not sure if VLEDs discloses their nominal voltage ratings for their LED replacements. I know they're rated for 12v, but how tight their tolerances are is a different story.

If you do happen to get a new set of LEDs, try putting a small resistor in series with the LED itself (a couple hundred ohms should be fine). If they still burn out, I'm out of ideas. Surely dirty/fluctuating power isn't good for the LEDs, but they shouldn't be dying left and right due to undervoltage.

[samir0189]

I put regular "bulb-colored" bulbs in there now. lol Better than the ew stock green condoms. I am gonna look into gauge overlays.... lol.

[DGAF]

Hello guys. I just wanted to coment that some LED's are not dimming capable but some are. I have LED's in my dash board and am always playing with the light output depending on my mood and never had a problem. you should check maybe you are having a bad contact on the actual socket where you are inserting the LED. Good luck

[lagos]

If you do happen to get a new set of LEDs, try putting a small resistor in series with the LED itself (a couple hundred ohms should be fine). If they still burn out, I'm out of ideas. Surely dirty/fluctuating power isn't good for the LEDs, but they shouldn't be dying left and right due to undervoltage.

All automotive LEDs already have resistors built inside of them.
The ones from V-LEDs claim to operate at 12-14v, but I guess as with all of them, your results can be hit or miss.

[richee3]

Try to bypass the dimmer all together. You could do this with a small paper clip in the harness plug.
Remember that the dimmer is a small potentiometer (like a vol knob in an old radio) and those are known to go bad over time. Maybe yours isn't sending out enough voltage to begin with.

That may very well be it, Lagos. I have another ignition trim panel from my parts car sitting in my barn. I'll go ahead and swap that on next time I'm putting new LED's in my dash and see what happens.

solidxsnake, I've been needing to buy a new volt gauge for a while, so this is giving me a good excuse. You're exactly right though, V-LED's does charge a lot for their bulbs, but I've always heard good things. I have their bulbs in my gauges now, and I only need one more, so I figure I'll just buy more of what I already have.

I remember seeing a thread a while back of what one guy did for LED's behind his gauge cluster. I've been meaning to dig that thread up lately, so I'll post it up here and see what you guys say about that, if you think it might help anything.

[solidxsnake]

I finished putting LEDs in my cluster (along with replacing all of the SMD LEDs on the stock headunit... we'll save that for later).

The dimmer circuit definitely seems like a "dumb" circuit, where it's a pot that controls the +12 to the lights. I dimmed my LED clusters back and forth to no problem. Again, I've never come across an LED that will burn out from under-voltage. I'm not saying it isn't possible, but I've just never experienced it, no matter how cheap/expensive the LED (and I've been working with LEDs in hundreds of different electronic devices for well over 6-7 years). I feel as if you may have just gotten unlucky.

BTW, my cluster looks GREAT with these LEDs. They're 4000mcd 5mm LEDs I picked up from Mouser. Bought 50 of them for $16 (32 cents a piece... very expensive for bulk, cheap LEDs IMO). Link: http://mouser.com/Search/ProductDetail.asp...y593-VAOL-5LWY4

Pics will come soon as I'm done with my CC.