LEDs, e-marking and MOT

[I-S]

I've been doing a bit of research, and figuring out how to do a full LED conversion (except for headlamps and sidelight bulbs - you'll see why) on the car, but have come across something...

Bulbs that are legal for road use in this country carry an E-marking. So far it seems that there are no LED bulbs which carry this marking.

However, I suspect that the car would still pass MOT (and have been advised so by several LED bulb suppliers).

So it's rather a grey area. However, the thing that concerns me is that LEDs will be a noticeable change externally (sharp on/off) and that the police may pick up on this.

Otherwise, it seems entirely doable...

382 for front and rear indicators
7443 for stop/tail
501 for side repeaters.

I know 7440s go somewhere (reverse? Fogs? 3rd brake light?)

The sidelights are 233... however, the reason not to go LED on them is not only that every single LED conversion I've seen hasn't been anything like legal, but also that it's a bad idea to put a LED into the high-temperature environment with the main headlamp bulb.

Also, the indicators will need load resistors. This can be minimised by using a single high-power load for all three bulbs (assuming that they're all wired in parallel, which is likely). Not a real problem though.

Also, the interior bulbs can be LEDed too, although I don't recommend it for the dashboard illumination as the LEDs can't be dimmed.

Does anyone know more about the E-marking situation?

[Big Ian]

it's a bad idea to put a LED into the high-temperature environment with the main headlamp bulb.



:inquisiti ...why?, i had led powered homemade angel eye's in my headlight's /yes and worked fine infact :smug: they worked better than the kit i bought at first /yes

[Nick Mann]

So what about the latest BMW's and VW's that have LED rear lights? Are they illegal?!? :rolleyes4

[I-S]

No... the OEM fitments are E marked.

Ian - that may be why the originals gave up. They won't have a long lifetime at elevated temperature.

[I-S]

I have now sourced an E-marked 501 repeater bulb...

[pezza]

Hmm this is interesting... (but slightly OT)

I had problems in trying to use LEDs for my front indicators... I was advised about resistor packs etc but in some cases, I was advised that the flasher units needed to be changed?

the bulbs work straight across the battery but not from the socket?

Think Zedy mentioned about the polarity of the switching circuit but cannot quite remember?

Isaac have you tested repeaters yet? (or anyone else used LEDS?)


The place I bought these from stated they should not fail MOT either? But then they were trying to sell me something so... :inquisiti

Cheers

Pezz

[I-S]

If the bulb is E-marked (as these ones I've found are) then there's absolutely no justification for them failing MOT.

A load resistor will make it work... the electrical system will know no difference between a bulb and a resistor. The LED has a polarity which means it must be fitted the correct way around.

[pezza]

OK... will check out load / resistor pack if I can...

I know the LEDs have polarity but it was the issue with how the flasher unit worked with leds...

Any ideas for the value of resistors/pack to solder in?

Cheers

[I-S]

Depends on which bulb.

For a 5W bulb, that's about 0.5A at 12V. Thus 12/0.5 = 24ohms and that will need a power rating matching the original bulb (actually you could probably get away with less because at worst it's on a 50% duty cycle, but better safe)

For a 21W bulb that's 1.75A at 12V, giving 6.8 ohms.

If you wanted to use a single load resistor and replace all three bulbs with LED bulbs you'd need 3 ohms, 50W.

[pezza]

Oh the days of Ohms law etc.. :inquisiti

How hot would those power resistors get? Bet they are not like the weedy ones from those electronics kits..

[Beastlee]

Sorry to revive an old thread but I've been looking into LED bulbs for both our cars and figured this was a good place to add my questions and possibly add some relevant info.

I've seen the LED indicator resistors and they seem to have nice sized heat sinks on them. I'm guessing they get pretty warm so I wouldn't recommend putting them near anything that can melt.
I'd like to know if we can use the new relays that have no problems with LEDs. Can we use them and if so which one should we use?

Reading a couple of the ebay ads and a few other places I believe the LEDs will dim with the dimmer, is this true? I also noted comments that they provide only a pinpoint of light on the dash, with the newer tower types can they be used for the dash and all the other backlit items?

I have an HID conversion and I know they are supposed to run cooler, can I use the LED 233s with HIDs? I hate fitting these dammn things into the headlamp housing so putting LED ones in would suit me perfectly. I found a few with metal cases, will this help keep them cool?

Does the reduced load by using all the LEDs help improve alternator/battery life? In theory I guess it must reduce alternator load too and hence improve the engine's efficiency?

I think I'll also do my Aircon unit as I'm fed up of not being able to read it when the lights are on during the day. I always have my lights on when driving (day and night), it's a safety thing I like to do.

Thanks for any info.

[Turbo_Steve]

I'm not sure LEDs will dim all that well, Lee....they've got a voltage threshold where they simply switch off (usually around 0.7), and the reduced current they pull means most dimmer circuits behave differently. Do you not have a High-Contrast dash?

The aircon unit definitely needs a different light source, however the LED installs I have seen appear to be VERY bright at night, and I absoloutely cannot stand glare. I have been looking for a compact EL panel to do the job instead...or maybe two sets of LEDs....one permanently on and the other on the lighting circuit. So when you put the headlights on, it turns off the second LED. Both run through a piece of smoked plastic to keep the brightness down, but during the day the second LED compensates.

[n13l pm]

My interior LEDs do dim but like steve said they have a voltage threshold so in the final stage of dimming it just switches off. I reckon about 80% of the dimming procedure takes place in my car. they do however look very good, they light up the whole interior with a crisp white glow.

Sidelight LEDs just never last IMO, iv tried two different sets now, one with the big metal heatsink aswell.. they did live longer then the standard LED ones but not more then a year and I only clock in 4k miles a year. oh yeah and I got HIDs aswell.

I replaced the aircon units bulbs with LEDs using the guide from Gly and it looks way better. you can use choose the LEDs mcd rating according to how birght you wish to have it.

[Turbo_Steve]

Do you get much glare at night?

[pezza]

Sidelight LEDs just never last IMO, iv tried two different sets now, one with the big metal heatsink aswell.. they did live longer then the standard LED ones but not more then a year and I only clock in 4k miles a year. oh yeah and I got HIDs aswell.




My LEDS lasted till I sold the car when I switched to HIDs. (1.5 years +)

I assumed that the heat from the standard headlamp bulbs killed LEDs in a matter of days...

I did not use any with heatsinks i think I got mine from http://ultraleds.co.uk/
they were 7 or 9 bulbed units wjhich worked a treat.. very bright. I did not have any problems with MOT either.

[Beastlee]

Thanks for the info guys, I think I'll just replace the main ones and leave dash and sidelights for now.