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Discussion Starter #1
Has anyone figured out a fix to get rid of the LED afterglow other than adding a filament bulb to the line?

I changed my map lights finally using the floss lasso technique :laugh:
Only problem, is now that the one OEM filament bulb is out, I either get afterglow in my added visor strip if the map lights are off, or afterglow in the map lights (whichever is on, or in both if both on)
 

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bump, anyone manage to fix this? This HAS TO be whats causing my batteries to die so fast. A brand new battery every year or 2 doesnt make sense.
 

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None of my LEDs have afterglow. I know it is a problem for a lot of people on here and I wonder if it depends on model year or how much current the replacement LEDs draw. I have LEDs in the trunk,dome,cupholders and underdash and none of them glow when in "OFF" mode. Wonder if the 47uf capacitors I installed in parallel has anything to do with it? But I have no afterglow.
 

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It doesnt sound like you do, but are there any filament bulbs in these circuits?

My trunk has no afterglow but the OEM bulb is still in there
 

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No I don't have any bulbs at all on these circuits.
 

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Last night I noticed two very faint lights as I walked up to the front of the car. Looked in and saw just a little light coming from my LED map lights. LEDs don't use much power so they probably aren't drawing to much. But still...
 

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There is a whole thread of many pages about this...

The reason you get an after glow is because for some unknown reason, there is a constant very low voltage which is always circulating the BCM. The reason why this low voltage is effecting some circuits is because your replacing regular bulbs with LEDs, which need much less power to operate. so when you Replace regular bulbs with LED's, you have much less load on the circuit, resulting in the slight glow of those LED's.

To resolve this, you will need to either keep existing regular bulbs and add LEDs, or add a load resistor in place of those bulbs. It also depends on your LED's, obviously Coby picked a good set of LEDs, they actually compensate for the load, so either get the same LEDs as coby, or add something which will use more power than the LEDs, or a load resistor.

LEDs are not lame, you just simply do not know enough about what your working with to get it working right.
 

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John, I think you're misunderstanding my previous statement. I've done a number of successful LED projects and am familiar with everything you said. I'm just looking for a good, safe solution to this problem, as is Acotu. That's why I posted in this thread.
 

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Ive read through the other threads about this, and was a part of most of them, but no one had a sure fire way to eliminate the glow. Its not a huge concern as technically the voltage is still there in the filament bulbs also, its just annoying that that energy is being used and slowly draining my battery.

Adding in a resistor doesnt really fix the problem either, just masks it. Granted it would take away the glow, but the bigger concern for me is stopping the current flow which probably isnt going to happen short if installing a toggle switch
 

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I'm curious what voltage the BCM is sending to these lamps with the car off and doors closed. If I measure it we might have a better idea of what's needed to solve the problem.

What about wiring a diode inline with the constant and see if that drops the residual voltage enough to shut them off? I will look up the wiring and maybe give this a shot sometime over the weekend.
 

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I checked my lights a little while ago. The map lights have a little glow but the plate light is totally off. Hum...
 

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I'm beginning to think that the lenght of unterminated wires in the car might be acting as a big antenna and that LEDs being diodes maybe rectify the standing wave and glow. I tried measuring the DC voltage before and my meter read very little voltage but the afterglow would disappear when I would put my meter in parallel. But I never thought of measuring AC voltage on the line. Meter might not read it anyways if it's RF. After I added 47uf capacitors here and there to have my LEDs kinda fade to off instead of a quick cut, my afterglow disappeared and I never bothered to check any further.
 

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Discussion Starter #14
I'm beginning to think that the lenght of unterminated wires in the car might be acting as a big antenna and that LEDs being diodes maybe rectify the standing wave and glow. I tried measuring the DC voltage before and my meter read very little voltage but the afterglow would disappear when I would put my meter in parallel. But I never thought of measuring AC voltage on the line. Meter might not read it anyways if it's RF. After I added 47uf capacitors here and there to have my LEDs kinda fade to off instead of a quick cut, my afterglow disappeared and I never bothered to check any further.
Im going to try the capacitor idea once i get settled in (moving in a few weeks). I like the gradual fade out option and if it fixes the glow, even better :)

Only certain lines are giving glow...actually, only the map/dome line.
 

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Coby, I read elsewhere that someone solved their problem by using a rectifier. Seeing as how electronics are your specialty, does this sound like an acceptable solution?

Otherwise, I'm interested in knowing where you placed your capacitors.
 

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Not really a rectifier just makes sure U don't reverse polarity on LEDs. Now you guys have me intrigued again.
 

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LED bulbs are not draining your battery. Plain and simple. They draw so little power. My GPS plugged in for a week doesnt drain my battery.
 

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It's not the draining of the battery it's the fact that it's still "ON" when it should be "OFF"
 
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