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LEDs don't turn off.. WHY WHY WHY

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Old Sep 26, 2009 | 08:13 AM
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Default LEDs don't turn off.. WHY WHY WHY

Just installed LED map/dome lights and they do not turn off all the way. They still have slight current draw and stay lit. What the hell? Anyway to fix this?

Both my map and dome lights stay on.. I figured they would turn completely off eventually but i came back outside to take out the trash at 3am and they were still on!! It was 6 hours!
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Old Oct 2, 2009 | 07:17 PM
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Sorry it's not the answer to your question but where did you get your Led's from?
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Old Oct 2, 2009 | 09:00 PM
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It happens quite often when people put LEDs in for their interior lights. It happened to me at first too, and was quite noticeable when it was really dark out (no moon, cloudy, etc). Basically, there isn't enough load on the circuit to completely turn them off - since LEDs take so little power to light, you are seeing what residual power is still left in the circuit that a regular bulb would just eat (and not be able to produce any light since they take a fair amount of power to do so).

Bottom line: here's what worked for me.

I'm gonna guess the dome light in yours is the same style as in mine - a festoon bulb. The first festoon LED that I bought used regular LEDs instead of the newer surface mount type. The map and dome lights would stay barely lit with that festoon in place. I tried a different festoon, this time with SMT LEDs, and found that they put enough load on the circuit that it kept the interior lights from being dimly lit.

I don't remember what exact part number I put in there, but I know it was from Super Bright LEDs, and it was the one with the most SMT LEDs that would fit in that size, all downward firing.
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Old Oct 13, 2009 | 01:29 PM
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i bought my cool whites from superbrightleds and they stay lit ever so slightly. perfectly normal.
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Old Oct 15, 2009 | 12:21 AM
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Originally Posted by futuref-body
i bought my cool whites from superbrightleds and they stay lit ever so slightly. perfectly normal.
Have a part number from there? I was looking at doing the dome, map, little door lights, license plate, and backup lights. Found the part number for the dome and door, but still searching for the correct part numbers to get for the rest.
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Old Oct 15, 2009 | 11:28 AM
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Originally Posted by green28
Have a part number from there? I was looking at doing the dome, map, little door lights, license plate, and backup lights. Found the part number for the dome and door, but still searching for the correct part numbers to get for the rest.
havent done the backup lights. i wired up my own leds for door lights and license plate. but as for the map and dome- map=4410 led festoon bulb x2 (i bought regular and havent tried the highpower) dome-4410 rigid loop festoon
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Old Oct 15, 2009 | 01:28 PM
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you could also put a resistor in line with one of the wires that go to the dome light, that should fix you're problem
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Old Oct 15, 2009 | 06:35 PM
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I bet the "switch" for the lights is really a transistor
somewhere, with enough leakage that LEDs can be
biased enough to illuminate. It's not like bulbs where
current has to be high to get out of infrared and be
visible.

A series (inline) resistor will only reduce, but not
kill the through-current that's making the light. You
need to get the applied voltage to be less than the
forward voltage of the LED.

A shunt resistor across the LEDs is what you need,
something that will let less than 1V develop from the
leakage when off. Get a voltmeter on there now, I bet
you see 2-3V "float". Try 1Kohm to start. You have to
be appropriate for whatever the series resistor that's
already there, is. If you can find that and read the
code then maybe a more accurate recommendation
can be made.
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Old Oct 15, 2009 | 09:03 PM
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you could wire in a relay aswell
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Old Oct 16, 2009 | 01:44 PM
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I thought about the relay idea myself, sounds like a pain in the ***.

I replaced all 3 of my interior light with LED's(2 in the mirror and the dome).

They all ******* glow when they are suppose to be off.

This does not put a significant load on the battery. I ran my DVOM in line for a day to see the draw. I mean it is in the .01 range(I think 0.02). The BCM takes more to run when in standby.


Sorry, the true solution is to let it go.


Or fab up some other ****.
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Old Oct 17, 2009 | 11:38 AM
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Refering back to what I originally posted, I'm going to ask this question to all those with this problem:

Are you using LED bulbs that have regular LEDs, or the surface mount variety? If it is a surface mount, it'll basically look like a white square that is soldered to a circuit board...
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Old Oct 17, 2009 | 08:27 PM
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What you posted, seems correct and is why I propose
a shunt resistor in the circuit to suck up the leakage
current.
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Old Oct 17, 2009 | 11:00 PM
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I don't even know what a shunt resistor is or looks like...
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Old Oct 22, 2009 | 10:00 AM
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A diode should solve your problem spiced in between the positive and negative wires . It looks similar to a resistor only the body is black with a small white line at the end .
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