Author Topic: power consumption to (reverse bulbs, indicator bulbs etc) LED bulbs  (Read 1130 times)

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Offline newway

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Dear all.

I have a few questions that confuses me when I want to switch my incandescent bulb (reverse lights, indicator lights) to LED versions, and hope anyone that has done so can answer these.

From what I read, some LED lights will cause warning lights, or fast flashing for indicator LED lights. This is due to the low power consumption of LED causing the car's computer to think something is wrong with the lights. Many LED vendors then say their product includes 'a load resistor' or 'decoder' to fool the computer by adding a resistor to recover the power consumption. BUT, wouldn't this go against the reason to use LEDs, which is to save power?

For example, let's say my old incandescent bulb uses 16W, and a new LED uses only 6W. Then a resistor of a working wattage of 10W is require, which will just be dissipating heat?

Is there something I miss? Thank you

Offline moozmooz

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Re: power consumption to (reverse bulbs, indicator bulbs etc) LED bulbs
« Reply #1 on: January 07, 2018, 02:20:59 PM »
There's an old saying. If it ain't broke, don't fix it. There are loads of potential problems when you start messing with "clever" car electrics, especially using parts from less than reliable vendors, so why make problems for yourself? When you say "many vendors....." , are these established reputable vendors or what?

Offline StevenRB45

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Re: power consumption to (reverse bulbs, indicator bulbs etc) LED bulbs
« Reply #2 on: January 07, 2018, 03:08:57 PM »
A Mazda 3 doesnt have bulb warnings, as a result for led lights you dont need resistors (With one exception which I'll get to), people usually fit them to increase the draw of leds as some cars will read this as a blown bulb due to the low power consumption.

The exception is indicators because the relay is reliant on the draw to flash at the correct speed. If you fit led indicators you will need either resistors or a different relay.

Offline newway

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Re: power consumption to (reverse bulbs, indicator bulbs etc) LED bulbs
« Reply #3 on: January 17, 2018, 06:22:26 PM »
A Mazda 3 doesnt have bulb warnings, as a result for led lights you dont need resistors (With one exception which I'll get to), people usually fit them to increase the draw of leds as some cars will read this as a blown bulb due to the low power consumption.

The exception is indicators because the relay is reliant on the draw to flash at the correct speed. If you fit led indicators you will need either resistors or a different relay.

interesting, many thanks!

Mazda 3 Forums UK

Re: power consumption to (reverse bulbs, indicator bulbs etc) LED bulbs
« Reply #3 on: January 17, 2018, 06:22:26 PM »