Reduce 12v

[ken o]

How can I reduce a 12v line powering LED gauges to a lower voltage to reduce the illumination? I have it connected to the dimmer switch but the LED is much brighter than the other lights.

[Nexus Flux]

Here are some great how-to's pertaining to car wiring Linke

Give me a sec an I'll try to find the article you need

[Nexus Flux]

LED's don't dim like incandescents, but a 470 to 560 resistor should take you down from 12V to the typical 5V that most LED's run on. Or you can get some 12V LED's and not worry about the resistor.

Here are a couple of articles that should give you a pretty good info
Link 1
Link 2

[ken o]

They have 12v LED in them. But the delta from bulbs in the OEM gauges to the LEDs in the gauge is too much. When I turn the dimmer all the way down the LEDs will dim but are still to bright.

What about heat generated form the reduction?

[goofygrin]

Cover the LED: http://www.leddim.com/

[sammm]

[ken o]

Good idea but it would block the gauge. I thought about amber tint but think it would be tough to see on the track.

[wrx74]

[Nexus Flux]

A 560 Ohm resistor will only disipate about 180 mW of power, so heat from a single little resistor should not be that much.

Here is a little calculator that might help you determine exactly how much resistance you need, sepecially since I'm not sure how many LED's there are in the circut.

[ken o]

Going to try and go to RS tomorrow to pick up a resistor. I have 3 gauges, each with and LED powered from one source, power is in sequence from gauge 1 - 2 - 3. I connected a 6v battery and the illumination was perfect.

Do I pickup a 560 Ohm resister or a 300 Ohm to drop to 6v and wire it in to the positive before the first gauge?