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Discussion Starter #1 (Edited)
I recently changed the dome light bulb with a bulb that contains red leds. I have attached a picture of it. My peoblem is that now the dome light never sompletely goes out The switch is set for the light to go on when the door is opened and off when the door is closed. When the switch is set for the light to be turned off and not work at all the light does go completely off. My theory (or at least what I have told my wife) is that leds take much less power to light up and that the normal bulb that was in there before needs more power to light up and that the current that is reaching the led was always there but just never detectable with the regular dome bulb.
 

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I would agree with your assessment. Using a parallel resistor across LEDs to bleed off the leakage current might be something you could try. Just make sure the power rating of the resistor handles 12 volts so it doesn't overheat.
 

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I am still a little surprised you are actually seeing something. I understand the concept of what is occurring but the lamp is controlled on both power and ground side. The power side I understand - there is a "wake-up" circuit inside BCM used to sense when a lamp is turned on. I didn't understand the the ground side but maybe there is some internal diagnostic circuitry on that driver which is enough to make your lamp glow.

If you leave vehicle for 1/2 hour with everything off is it still glowing? By that time the BCM would truly have gone to sleep and turned off the direct battery feed to the lamp (leaving only the "wake-up" input active).

Does the dome lamp (when switch in middle position) only come on full brightness when you open a door? I just ask this to make sure you wired new lamp correctly.

The only potential problem would be if your lamp some how "teased" the BCM into thinking a lamp is being turned On/Off. I don't think that is occurring but if you now start running into dead battery conditions I would start looking at your new dome lamp as the culprit.
 

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Discussion Starter #5
The car has now sat for 13 hours, I peeked in the window and the done light still has a subtle red glow. All I did was change the bulb from the original to this red led one. nothing else. When the switch is in the middle, like it is now, and the door is opened the light does come to full brightness and then as it should it would slowly dim to the point where it is now instead of to the point of being completely off as it did with the original bulb. With winter coming to Illinois the last thing I would like to do is send the wife off in car that has the potential of coming up with a dead battery. Not only for the safety issue of it but also because I would probably never hear the end of it lol
 

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One other thing you might try (just as a test). Run the same scenerio where vehicle is going to be sitting for 1/2 hour or so. This time (if you have them) turn on one of the interior map lights and then shut off ignition and close doors. After 20 minutes the map light should go off automatically because the BCM shuts off power to it (and to dome lamp). However the map light is still hooked up.

Under those conditions is your new domelamp still glowing? This other bulb should act as a pretty good bypass load to prevent it from glowing.

Even more interesting if you could have left the window down (so you don't have to open door) reach in and cycle the map light you left ON to OFF. Does your dome light start glowing again?? If you turn the map light back ON at that point (still without opening door) I think the map light WILL come on because IT will wake up the BCM like I mentioned in previous post. Dome lamp under that condition probably stays off (as long as door not opened).
 

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My theory is the transistor is always feeding some power to the factory bulb, the amount is so small the lamp will not look on. The led light draws so little power it looks on. A sure test would be a check for battery milliamps with everything off and see if it is within factory specs.
 
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