- My model of MX-5 is: _2007 2.0 Sport PFHT
- I’m based near: SE London
- I’m looking for technical help or recommendations on: Fitting LED lights all round but not wanting to cause any electrical issues flagging up.
Thanks.
No, your quite safe fitting LEDs.
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Excellent, thank you.
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As long as they aren’t the cheap ones from eBay, I’ve had to replace a few of them the previous owner fitted to my car because they seemed to go wrong quicker than standard bulbs!
It tends to be the driver that fails (power supply) not the LED.
Be aware cheap drivers cause a lot of noise, they switch the LEDs hundreds of times a second to get the average voltage and the back EMF puts ripples into the supply system. The net result is you get poor radio reception. Cheap chargers are the same, eBay specials, amazon fakes, they all get left in the power socket and ruin your radio reception. It can cause other problems too, endless possibilities.
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Any recommended LEDs that you have used that don’t have cheap drivers?
No sorry. I don’t mess with changing the lights on cars, I’m an industrial electrical engineer. I leave car lights well alone, they work so I’m happy.
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Hi, I’ve replaced my stop/tail lights with these: https://www.autobulbsdirect.co.uk/7443-twenty20-cree-led-12v-580-canbus-wedge-bulb.html
(Go for the red ones) They are longer than the original bulbs, but they do fit and the light is even with no hot-spots. I like the LED look for brake lights, and the instant on matches the boot lid brake light.
I’ve also fitted LED indicators in the rear from eBay. These work well and don’t cause the any hyper-flash. They look cool but they are VERY bright. The jury is out on whether these are too bright.
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Could you please try putting your hand on one of the lenses to try and gauge how hot the bulbs are getting?
I would rather like to get a pair of LED stop/tail bulbs but @RichardFX is cautioning against it as he fears excess heat if the bulbs are suitably bright.
Don’t burn yourself though… 
No CANBUS ON NC.
However with any generic LED lamp, if it claims to work with CANBUS, then heat might be problem, and it sometimes does not have much correspondence to the actual light output.
An example with T10 W5W wedge bulbs, as used in NC front sidelight.
I have a collection of T10 white bulbs, mostly 4000K, none fitted in the NC for various reasons. Today as a test I connected them all at the same time to see how the brightness varied between them. I also measured the temperature of each after ten minutes or so, and again at fifteen to see if any further rise. At various times in the past I also measured the current each one took from my bench supply set at 13V.
Here is a picture summarising the test, top half lit, bottom half unlit so you can see the bulbs hooked up.
The LED at 3.1W has CANBUS cheat resistors built in. On a previous test a couple of years ago the Sodial got so hot after half an hour one of the two 220 Ohm shunt resistors unsoldered itself and dropped off, hence the least efficient lamp (30 lm) now only running at 75C above ambient today (20C) for an actual 2.4W.
The Katur at 2.6W is putting all that into the LEDs, but it is much too bright for a sidelight, great for occasional duty inside the car as an interior or boot light though, and it might pass a CANBUS test.
The other LEDs will fail a CANBUS test. Some of the six LEDs need correct polarity to light.
My latest lamp under test is a Noobibaba from China via Az Vine today, and it is surprisingly good, with the regulation 50 lm output from only 0.25W of power (nominal 0.5W). It also aims forwards, perfect for the front sidelight diffuser lens on the NC.
The most efficient bulbs are the Katur (170 lm/W and ten times too bright) and the Noobibaba (200 lm/W).
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And the Noobibaba runs at only 10 degrees plus
Noobibaba is £8 for 10, seems like it’s worth a shot, they also do a 1w version.
My main concern was the rear indicator as my lens have been tinted red and was told the amber bulb would show as red though the lenses red plastic but I did try it with a cheap LED and it was perfectly orange. I would guess as its an indicator and not constantly on that heat shouldn’t be an issue.
Yes, I was offered the choice of either, and in Blue or Cool White, but chose the “0.5W” Cool White as it was the correct lumens and colour and would run coolest.
I was pleased to measure three from the packet each at 19.5mA from 13V for about 250mW.
Most (but not all) non-white LEDs put out narrow band monochromatic light. So an Orange LED has no Red light. However the red tint will have reduced the brightness, depending on how steeply cut its colour filter is.
That’s crazy I saw people going for green bulbs and all sorts, saying it was the only way to get orange through a red lens.
I had a generic strip of LEDs about 4, wired to a 10v drill battery, was easy to see it was orange.
Will probably go for branded LEDs and hope for the longevity, from your test Osram and Phillips also seem rather decent, at least for the t10.
If the standard bulb is orange and shows through the red tinting as orange, there’s a very good chance the orange LEDs will show through as orange as well.
Presumably, the red tinting is very thin and the orange will easily overpower it.
Do they do a stop/tail version???
Interesting comparison, thanks.
I see that none of the LEDs (even the stupidly bright ones) get up to the 85 degrees of the filament lamp.
Have you done any testing within batches of the same lamp to see whether there are any major variations within those batches?
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So, its the extra resistance of the canbus friendly LEDs that makes them run hot and potentially self-destruct, therefore for our NCs, we could do with non-canbus versions.
I have never tried it, have spare lights in the house. It’s just that the standard rear lights are clear where the indicators are so was never sure if the orange colour would pass though red tint when original it wasn’t red.