A Buddy gave me a handful of great looking LED Dash indicator lights, not too Spacey-looking so I thought they would be great on my 28A Close-Cab pickup dash. I wired one into the headlights for a Hi-Beam indicator, and another into the Idiot-Light circuit for Alternator ..... the Alternator light 'Flashes' when I turn the ignition key on or off, the Hi-beam indicator does nothing. The lights worked fine and lit steady clipped directly to 12V ... I expected them to light steady when they got 12v in circuit ... Howcum they wont? I am a 'OLD' greasy hot-rodder, be gentle.
You know LEDS are "directional" - they have a + and a -. The 'diode' part is actually a one way check valve for current. So- assuming the LEDs are actually rated for 14-15 volts - try reversing the connection on the highbeam and see what happens. On the alt idiot light - that light is actually also used to apply a slight load to the alternator so it can energize. It's likely that the LED isn't drawing enough current to excite the alternator. On mine, the LED alternator idiot light stays on until I rev the motor up a little. The way to fix that is to shunt the LED with a resister across it's terminals. That will increase the load the LED takes. I don't have resistance values for you though- I'd have to do some math. Perhaps someone else may be able to shed some light?
Just like the previous post says, they're directional. Which means if you test them on 12V with + to one side and they work, you want to make sure you hook the + side to that leg when you install it. I use 12V LEDs in my custom gauge clusters all the time, and I can't tell you how many times I've gotten distracted and gotten them accidentally switched up after they're all together. On the bright side, they're usually rated for some obscene life expectancy of 10,000 hours or something like that. Never have to worry about one burning out on you. Also, if your indicator lenses (turn, brights, etc.) on your gauge cluster have gotten fogged over or shrunken/rippled from age, you can remove the lens and replace it with a clear piece of plastic, then install a green/red/blue LED in its place. Looks cleaner, and they burn so much brighter.
NOPE ... I did not know/or forgot about "directional" I think that will fix the Hi-Beam indicator (switch Ground and Power?) the Alternator light might be a different animal .... the concept there starts out being kinda-screwy ...("the light is grounded and "on" while the alternator is 'not' generating and turns "off" when the 12V comes 'from' the generator - ground is 'lost') Thanks David for the heads up ... old guys can learn. btw: I am wiring this thing pretty much from scratch ... "just keep adding layers"; -that guy, probably had never heard of a LED though I know they have been around since the Sixties ... the guy I should have listened to took great pains to explain why we correctly speak of "A LED" instead of "An LED" -A Light-Emitting-Diode" I'm betting he told me about 'directional' too; problem is I've slept since 1965. -J.
@Ragtop Thanks ... and for the Monet thing too, I'll be adding that one to my repartee ... My current favorite is: "If you don't drive 'em; you might as well buy furniture."
Thanks Guys, Just went to the shop reversed some leads ... everything works like it should! I expect the Alternator light will work correctly when I get the Alternator installed, the principal is taken care of .. ground will be gone when it's generating. Only problem I see now is, LED's are Bright! , what might save me is the light is focused and will not be in my line-o-sight for the Hi Beam but will sure get my attention if the alternator light comes on at night
Yessir, they are. Here's another little trick... If the LEDs are installed in the actual cluster and you want to dim them a bit, you can replace a messed up factory lens (they dry up, shrivel, shrink, ripple, collect dust, become brittle, fall out, etc.) with a BINGO chip! You can order colored transparent BINGO chips online by the hundreds for just a few bucks (like three) in just about any color you can imagine, or even white! If they're too big to fit in the pocket, they're easy to file down to fit with a little emery cloth. A red lens over a red LED will knock it down about 30% or so. Just enough to make it a non-retinal searing indicator. If you want to dim it some more, stack two chips. OR, install a colored LED with a white chip as the lens, and it will not only dim it to the point of being tolerable, but during the day it gives your cluster a nice clean look. Some factory indicators for turn signals have the little directional arrows on them as well. Cut out your little arrow from some masking tape, center it in the BINGO chip, and mist that side with flat black hi-temp enamel. Install the chip shiny-side out, and viola, refurbished turn signal indicator. I like being able to change the factory-determined colors of my indicators, too. Want a purple indicator to match your interior? Install a red LED with a blue BINGO chip over it. Have fun! (Glad you like my little sig, too. )
Try putting a 300 ohm resistor (270 or 330 will work too) in series with one of the LED leads. Should lower the brightness by 1/2.
Thanks Gerg. I'm a "cluster junkie". I'll often buy gauge clusters I have ZERO use for other than to restore, or customize. Each cluster was a part of the personality of the make/model, and I think most often one of the more beautiful parts of the car. I'll sometimes sit for 36 hours (or more) straight, without eating or sleeping, working on a cluster I just got lost in the process of, just enjoying it come back to life.
Thanks for the 'tips' ... I may just use something to mask the Hi-Beam indicator. (I'm not sure what diam. a "Bingo-Chip" is or what one looks like ... I live in the Mid-West ...round he-yah we use corn-kernels for bingo. The actual lens diam on my lights is around 1/4" ... I'm sure I can find a way to dim it if need be. "Lost in the process" ... been there. Thanks Guys.
You need a current limiting resistor (as D2 Willys said before) or your LED's wont last very long (try about 30 seconds) as they appear as a short circuit without the resistor. Some of the new fangled high intensity jobs can be downright painful, even with the correct resistor in series with it. You can go as high as you like, resistor value wise, until it is comfortable to look at. As you increase the resistance you decrease the current through the LED, so if you have to go to 1000 ohms or higher, it wont damage anything. In theory, it will actually make the LED last longer! The only place where this WONT work, is if you use an LED as an alternator idiot light, then you will have to use a suitable globe or resistance to get your exiter diodes in the alternator to work.
These are bingo chips, amigo! Lol http://www.ebay.com/itm/100-Plastic...ltDomain_0&hash=item5d27599061#ht_1529wt_1270 http://www.ebay.com/itm/100-Plastic...ltDomain_0&hash=item5d27598a83#ht_1529wt_1270 http://www.ebay.com/itm/TUB-OF-GREE...ltDomain_0&hash=item5acf3a9861#ht_1894wt_1037 http://www.ebay.com/itm/TUB-OF-PURP...ltDomain_0&hash=item5acf3a98cf#ht_2014wt_1037 If you want to HIDE an indicator altogether, and it sets in a chrome bezel (as many do), go out to the Dollar Store and pick up a pair of cheap mirrored sunglasses. Cut a lens the size you need out of the sunglass lens. Installed mirror side out in the chrome bezel, it blends right in with the chrome, looks like all one piece. You'll still see the LED through it when it lights up though.
They do sell 12V ready (already current limited internally) LEDs, so he might be using them, but adding more resistance won't do any harm to the LED, only lower the intensity of the light emitted.
I'm surprised no one has said it yet, LEDs aren't traditional, they didn't exist before 1962. blah blah blah. I think LEDs are fine, but some would disagree.
The LED light was invented in 1927, so theoretically they COULD have been used as soon as they were publicly available... The first use of LEDs in an automotive capacity was the '84 Vette. (Ironically, I believe the Vette was also the proving grounds for fiber-optic dash indicators back in the late 60s/early 70s.) Traditional would probably depend upon availability if you ask me. Who knows what has and hasn't been used and went undocumented. But I ain't nobody.
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