Are there LED alternatives to the Optic Fiber leads?

lanciahf

lanciahf

True Classic
Can someone share a link to LED leads instead of using the optic fiber lighting? I have a couple cut optic fiber wires in my scorpion and I am scared of the dark. I found some threads but the pictures are missing.

Thanks!
Ralph
 
I have a set for an early X1/9. Sorry I can't tell you what size they are, other than they're tiny, or where you can get them. They are easy to construct all you need is a hot glue gun. Mine each have a small resistor installed inline. They work great, but now they have two wires to each, not just one fiber optic cable.
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VW did red for action items (switch gear) and blue for information (gauges and other displays), it worked quite well.
 
MikeHynes said:
I have a set for an early X1/9. Sorry I can't tell you what size they are, other than they're tiny, or where you can get them. They are easy to construct all you need is a hot glue gun. Mine each have a small resistor installed to keep the brightness down. They work great, but now they have two wires to each, not just one fiber optic cable.
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The resistors are there to limit the current running thru the diode, not for dimming.
 
Not really, there there to prevent the diode from blowing. Once a diode starts conducting it's basically a short circuit and will draw as much amperage as it can get. Diodes are usually dimmed by pulse width modulation.
 
Integrale is correct. You can though add additional resistance to lower the light intensity, however, not all LED have the same forward voltage specs. and the eye perceives the brightness of different colours differently to each other so if you are mixing LEDs you are going to have fun trying to get them to appear the same.
 
Thanks all, I clearly have a lot to learn about LED lighting. I'll edit my first post.

I have converted one car (except for the headlights) and I found it to be very easy to do, and relatively inexpensive. For that car I simply replaced the regular fiber optics bulb with an LED light. That works just fine for me, but I did see that replacing the fiber optics with the little LEDs resulted in much brighter indicators. If your fiber optics are damaged, these LEDs are a good replacement.

I do have a question about LEDs in general (pretty much on topic?).
I used LED bulbs similar to these to convert my car. They work very well.
Are the resistors already built into these lights? Or do these LEDs not need a resistor because they are designed to work with 12V?
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Another question.
I have some LED lights that I stripped out of a vehicle that runs on 24V. Can I use them on a 12V car? Will they simply be dimmer than they were on the 24V vehicle?
 
The LED chips themselves have a forward voltage of about 1.5V to 3V depending on the technology. If it is being sold as a 12V device, it needs to have a series resistor to limit the current.

For a 24V car, the resistors would need to be a higher value to limit the maximum current. When used with 12V, the current through the LED will be less and the device will put out less light.

In general, the light output of an LED is proportional to the current running through the LED chip. They do get less efficient with temperature so at high current (temperature) levels the relationship is no longer linear.
 
This has confused me a little. All of the LED's I've purchased were advertised for 12V and required no additional resistors. And many of them are listed as working for a rather wide range of voltages, also without adding resistors. I thought the main reason a resistor was added to any LED's was to prevent false error codes on more modern cars that sense bulb draw to tell you when one is burned out, or to make the incorrect type flasher work with them? Otherwise adding any resistance to a LED seems to negate one it it's biggest benefits - less draw on our very borderline electrical systems. As for dimming a bright LED, wouldn't it better to use an appropriate dimmer? Like the later type electronic rheostat that Karl mentoned? That also makes it adjustable brightness. As for "protecting" the diode, I thought that was another one of their big benefits - they last forever. So why would you need to protect it? All of the numerous LED's I've used have lasted for years without adding any resistors. Perhaps I'm missing the point of this resistor topic?
 
Most LEDs are in the 3V with slight variations for different Colors. I have been using the Green LEDs to make a poormans Voltage regulator for old vintage bike gauges that need a 7V regulator. All the 12v ones I have seen have the resistor on the anode side with shrink wrap. Here is the cover of the amazon LEDs that I use.

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Dr.Jeff said:
This has confused me a little. All of the LED's I've purchased were advertised for 12V and required no additional resistors. And many of them are listed as working for a rather wide range of voltages, also without adding resistors. I thought the main reason a resistor was added to any LED's was to prevent false error codes on more modern cars that sense bulb draw to tell you when one is burned out, or to make the incorrect type flasher work with them? Otherwise adding any resistance to a LED seems to negate one it it's biggest benefits - less draw on our very borderline electrical systems. As for dimming a bright LED, wouldn't it better to use an appropriate dimmer? Like the later type electronic rheostat that Karl mentoned? That also makes it adjustable brightness. As for "protecting" the diode, I thought that was another one of their big benefits - they last forever. So why would you need to protect it? All of the numerous LED's I've used have lasted for years without adding any resistors. Perhaps I'm missing the point of this resistor topic?
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The LEDs with resistors commonly sold have the resistor in series with the LED to limit the maximum current. If you connected an LED directly to a 12V battery, you would get a little puff of smoke and that would be the end of it. If you have a resistor in series with the LED so that it runs at a reasonable current, it is likely to last forever. These LEDs draw much less current than the incandescent bulbs they replace and their radiation patterns can be optimized better for certain applications which can make them even more efficient. Putting the resistor in series with the LED will not cause the device to draw more current. The same current going through the LED is going through the resistor, and the larger the resistor, the lower the current will be. You may be thinking of the resistors put in parallel with LEDs so they draw enough current to make a flasher work or for the car electronics to think there is a bulb there. The festoon bulb I recently bought for the overhead light had some electronics built into it that will supposedly let a CANBUS know it is there. It also makes it polarity insensitive so I am guessing there is a bridge rectifier in series with it as well.

At some point I plan to replace the instrument panel backlighting and center console lighting with LEDs because everything is a bit too dim. I need to decide whether or not to ditch the fiber optic system. With the cost and convenience of these LEDs with leads and built in resistors, it might be the way to go. I need to pull a switch out and see how they will fit. If I keep the fiber, I know I need to replace the one that was pre-kinked from the factory. It has always been about half the brightness of the other switches. Fiat could have made the switches a bit brighter if they used 1mm core single fiber instead of a 1mm fiber bundle. Usually the bundles are used where a tight bend radius is needed which is not the case in the center console. If you remember the 68 Corvette, it used 1mm core fiber as a light bulb monitor on the console.

I'm not familiar with the dimmers on the later models, but the 74 has a simple variable resistor set up as a voltage divider. I suspect it should be able to handle the instrument panel and center console so the two position instrument panel switch would not be needed (you would also need to change the resistors to make it work with LEDs).
 
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