LED Question

[u_couple]

Can someone help me with an LED problem?
Out of the last 5 mods I have built (simple 14500 box mods with an LED) 3 of them have lit the LED as soon as the battery has been inserted, now when I say lit, I mean very faintly!
I have checked, and double checked the wiring, and all is good.
I have narrowed this down to only happening with "colour changing" LED's , it never happens with single colour LED's. My problem is that the friends I make these for prefer the colour changing LED's (something to do with timing how long a drag they are taking)
Also, while doing a continuity test on my wiring I noticed that even my meter would light the colour changing LED's, but not the single colour ones!
I am quite "electrically challenged" and really can't figure this one out.
On all these mods I am using a 470k resistor (cause I have loads of them), so my question is, am I doing something wrong, or do I have a duff bunch of LED's ?
Any help greatly appreciated guys

 

[boomer2506]

Must be something in the swicth.There shoud be no power not even alittle at the led when the swicth is open.

 

[u_couple]

Deffo not the switch, I`ve replaced the switch and it`s still the same, but when I use a single colour LED, it doesn`t glow

 

[P1NkY]

Try cleaning the solder joints on the switch with a toothbrush soaked in isopropyl alcohol. Flux (either used separately or already included in the solder itself) can be the tiniest bit conductive, leading sensitive devices to "power on" mysteriously.

If this doesn't work, could you post a close up pic of the innards of one of the boxmods? You might have overlooked something; I do that all the time, lol!

 

[u_couple]

On the last two, I just swapped out the colour changing LED`s for single colour ones, problem solved !!!! But I`d still like to know what`s making the colour changing ones glow ?

 

[CraigHB]

The only way an LED can illuminate at all is if it's getting power somehow. You probably have a full time draw on the battery somewhere. It's possible the color changers have a lower forward voltage so they illuminate slightly where the non-changers don't. A wiring digaram would be helpful. Without it, it's going to be difficult to tell where you might have a problem.

 

[u_couple]

I think you`re right with the switch guys, when I am tinning the terminals on the switch, there must be a tiny amount of fluid getting into the switch, which in turn is allowing a tiny amount of power to go to the LED, not enough to fire the atty, but just enough to give the LED a very faint glow. I just built another mod, taking great care to connect the wires to the switch, and all is good ---------- so far !!
Thanks for all the help guys, much appreciated

 

[chingbo]

what kinda LEDs are you using? I just put one in my Reo Mini.
and I used these:
from ebay
20pcs Super Bright White SMD SMT PLCC-2 3528 1210 LED

and i got lots left, if you want a few I can send you some.
if you want pics of my Reo mini, lemme know

 

[DaveP]

I'd like to see the schematic, just for informational purposes. Do you have a JPEG?

I'd also like to see the spec sheet for both type of LEDs to look at the specs.

 

[chingbo]

I dont have schematics.. I just soldered wires to the led, pos (+) the reo's switch, neg (-) goes to the battery spring.
no resistors either, just thought to try and see what happens and it worked =)
That's it..

 

[DaveP]

I dont have schematics.. I just soldered wires to the led, pos (+) the reo's switch, neg (-) goes to the battery spring.
no resistors either, just thought to try and see what happens and it worked =)
That's it..

Sorry, I thought you were building mods, making the boards, and putting everything together from piece parts.

 

[chingbo]

that's ok, I know this is the modding forum

just thought i'd throw it out there that what I tried worked
if it helps anyone