Today at Atelier Kaz - ex-Honda R&D, F1, Indy/CART engineer

I have been testing the super bright LED festoon bulbs on
NSX and MX-5 for a few years now and fairly happy with it.
One of the LED at my ceiling light failed just after a year but
rest of them are still surviving.

The only problem is that the vendor in Japan is so busy with
other projects that he is putting lower priority with his LED business
and thus, being told that he won’t be able to supply the same spec
until some point later in April.


After talking with the owner,
decided to get almost identical one from UK vendor just for the
ceiling and the boot lights.
The rest will be covered by the classic design LED that is
good enough for the purpose.








The comparison.
The one from Japan at the top and the UK one at the bottom.

Almost exactly the same size/design except the UK one is
just a bit (1mm) longer with bit more yellowish cover
at the front.

To my surprise, this slight difference in the size caused
extra work for me but I’ll touch on this later.

The advantage of UK one is that as far as I know, it is surprisingly
covered by 1 year warranty which is very generous considering
the different temperature environment that each cars have.

LED itself will last for long-long hours but depending on the
internal circuit design for constant current and temperature
control, the actual usable life time could be significantly reduced.



For human eyes, colour temperature makes big difference in
how you feel the brightness.
Also I was told that one’s eye colour may cause some differences
in sensitivity although I can’t confirm this from my own experience
as I only have dark black/brown eyes........

Addition to this, the colour/shape of the beamed objects has huge
effects on how you feel about the brightness.


Unfortunately, my digital camera is partially dead and I can’t
change the white balance so it’s not going to be easy
showing the difference.







The one from Japan.
It’s cool white and feels the brightest for this price category.








The one from UK.
Slight hint of yellow but white.
This tiny bit of yellow colour makes it feel darker compared to the
one from Japan especially when just looking at the black leather seat
and the black centre console cabin but if you are reading the map or
place white paper underneath, it’s well bright enough.








The classic design LED.
The brightness feels like similar to the UK one.
It has two surface mounted LEDs so without the lens in front,
it may look odd but once the cover is installed, not a problem.

This will be used for the door courtesy lights and the
driver foot down light.


Despite being LED, all three managed to keep the fade out dim feature
at the driver foot down light.








The standard 5W bulb used at the celing.






The standard 3.4W bulb used at the door and down light.








When I tried to remove the passenger side red lens,
it almost dropped off.

Looks like one of the locking tab was already broken but
it could have been me although I couldn’t find the broken off parts.

If I can’t recreate the tab, I’ll replace it with new one at my cost.

Apology in advance.