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Discussion Starter · #1 ·
I know its been covered before but which LED bulbs do people use for the interior map spot lights?

I have tried searching, honest. every link to ultraleds i find for the bulbs you guys have used comes up with "product not found"

ive replaced the interior festoon bulb & both boot lights. I have replacements for the numberplate lights and side lights (was raining and dark so didnt do those tonight)

The ones i got for the sidelights are these:
http://www.ultraleds.co.uk/uh6w1w-bax9- ... -1269.html
i thought they looked like they'd fit in the map lights but they didnt work, so please, what do i need to get for them?

thanks

Mark B
 

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Discussion Starter · #2 ·
ok so i found the ones i needed. But they dont work. Do you have to do something special with theese ones?
thanks
 

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Naresh made me some custom ones - 6 LEDs in each! They look stunning.......

<<<<BUT>>>>

- You will need resistors
- They dont fade out anymore, they just switch off
- They take ages to switch off, so the first 30 seconds of every journey involves your interior lights being on or meaning you have to switch them off manually which can get tedious
 

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Adam TTR said:
Naresh made me some custom ones - 6 LEDs in each! They look stunning.......

<<<<BUT>>>>

- You will need resistors
- They dont fade out anymore, they just switch off
- They take ages to switch off, so the first 30 seconds of every journey involves your interior lights being on or meaning you have to switch them off manually which can get tedious
Really selling that to me mate :roll:
 

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I just looked on the Ultraleds website and they seem to have changed their product range somewhat. The map reading lights you needed were indeed reverse polarity. The images for their lamps are still on their server but the old links to product no longer work. I notice the 6 LED festoon lamp is also no longer there - that's a real shame :( as it gave a brilliant light 8) . It may be worth contacting them.

The fade out is affected by the use of LEDs as they stop working when the voltage gets low during the fade. e.g.

Incandescent lamp fade.....: 10, 9, 8, 7, 6, 5, 4, 3, 2, 1, 0
LED replacement lamp fade: 10, 9, 8, 7, 6, 5, 4, 3, 0, 0, 0

... but I don't understand Adams comments about the LEDs staying switched on. Are you sure your courtesy light function is working properly off the door switch Adam?
 

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Looking further on the Ultraleds site they seem to have replaced the 6 LED festoon:



... with this one:



http://www.ultraleds.co.uk/42mm-leds-fe ... -1461.html

The description says it's "buck driven" meaning there is a switch mode power regulator involved and it talks about the voltage range being 8V to 30V.

I was never convinced that the failures seen on some LED lamps were anything to do with over voltage, but instead due to thermal stress during the soldering process in manufacture. They still seem to be over worried about voltage - needlessly in my opinion.

Anyway, this means that if you use these LED lamps in the courtesy light position, then because of the way a buck regulator operates, it will maintain a regulated light output, as the TT lamp controller is trying to fade by reducing the voltage, but all of a sudden the regulator will no longer work and the light will go out.
 

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Discussion Starter · #12 ·
XTR said:


Could always bodge it!!!

I did, then when the reversed polarity bulbs came out, i bought a replacement light.
right, thats excellent, thanks.

so they sell reverse polarity bulbs so i dont have to do that, is that what you are saying? got a link?!?
 

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Discussion Starter · #13 ·
does anyone know the resistor value i need to add into these bulbs to get rid of the flickering issue?
 

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I've seen 330ohm being mentioned several times before for this purpose.
 

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XTR said:
John-H said:
I can't find the reverse polarity bulbs on the Ultraleds website either. I've emailed them about the discontinuations. I'll let you know what they say.
I think they were listed under ford focus map reading bulbs.
Hi,

You are correct in your assumption. They are the ford focus leds and i dont think they do them any more..... :(

I have them fitted .... :wink:

Cheers
Bobski
 

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Discussion Starter · #18 ·
ok i have modified my center light, reversed the pol on the map lights as the pic above. works great.

i can also confirm that a single 330ohm resistor accross the festoon bulb is enough to pull the relay in, if you have fitted LEDs to the vanity lights too (i have :D ) then you will also need a sinlge 330ohm on each of those.
Interestingly, once the relay has been triggered, any of the lights will work on their switch,regardless of having a resistor or not. So if your map lights dont have a resistor on like mine dont; they will flicker if operated by the switch. but if you turn on, then off, the main festoon with the switch, it pulls the relay on and the map lights will now work independantly.

Mark
 

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Meeerrrk said:
ok i have modified my center light, reversed the pol on the map lights as the pic above. works great.

i can also confirm that a single 330ohm resistor accross the festoon bulb is enough to pull the relay in, if you have fitted LEDs to the vanity lights too (i have :D ) then you will also need a sinlge 330ohm on each of those.
Interestingly, once the relay has been triggered, any of the lights will work on their switch,regardless of having a resistor or not. So if your map lights dont have a resistor on like mine dont; they will flicker if operated by the switch. but if you turn on, then off, the main festoon with the switch, it pulls the relay on and the map lights will now work independantly.

Mark
Well observed :wink:
 

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Discussion Starter · #20 ·
thank you sir.

great link in your sig BTW, been useful already :D
 
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