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Discussion Starter #1
Greetings All,

I replaced the dome light with an LED some time ago. I've noticed that there is enough leakage current to dimly illuminate, even with the doors closed. It's just a few mA, but enough to discharge the battery after prolonged storage.

Is the normal? Any idea if it can be fixed?
 

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This is normal, sorta. So, the car's electrical system was mainly built for bulbs. There's always a current going into the dome light and a few other bulbs.

The reason they don't glow (at least in newer 451s) is that the bulb itself naturally has just a little resistance...Enough to counter the current when the light is "Off".

Any non-CANBUS LED isn't going to have any notable resistance, thus you get the dim glow. To prevent this, buy a CANBUS LED. CANBUS LEDs have a resistor in them to emulate the draw of a light bulb.

Now, not all LEDs and not all smarts are built equal. Sometimes you'll get a CANBUS LED that doesn't work right. That's annoying. I've had the best hit rate buying CANBUS CREE LEDs. Those seem to have better resistors in them. As a bonus, they push out more light anyway. :)
 

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He's not mine
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My dome light has the foxfire glow. I'd say if it doesn't bother you visually, then don't worry about it. The car's electronics certainly draw far more current even when "shut down", making that LED's glow trivial in comparison. And, if what MM says is factual, even the incandescent bulb is drawing current, even though not apparent visually. Utter waste vs. nice glow, LOL.
 

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Hehe I like the idea of nice glow.

But yeah, remember early threads on this forum? Apparently quite a few 2008s and I think 2009s would dimly light the incandescent bulb when it was off. Then I guess smart made a rolling change one year and that issue disappeared.

I can't find that old thread through Google or the forum's search functions. Then again, it seems most really old threads are hard to find for me anyway.

This thread has a better explanation of how the dome light works:

http://www.smartcarofamerica.com/forums/f19/led-dome-light-help-39292/
 

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Discussion Starter #6
I find if my 2008 sits for more than a few days, the battery is depleted and it's a pain to access the battery to connect the charger. I've added a 12VDC socket direct-wired to the battery so I can float charge if I know it's going to sit for more than a few days.
 
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