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2017 Subaru Outback Premium
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Discussion Starter #1
I replaced the interior bulbs with canbus leds and somehow I fumble fingered it so now none of the interior lights work. Any suggestions? :banghead:
 

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2018 Touring 3.6R
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I replaced the interior bulbs with canbus leds and somehow I fumble fingered it so now none of the interior lights work. Any suggestions? :banghead:

“If it ain’t broke, don’t fix it.”


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Maybe a blown fuse? Check the fuse box right in front of the drivers seat. One of the 10A fuses is the one for the interior lights.
 

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2008 OB Limited 2.5i, Portland OR USA
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I replaced the interior bulbs with canbus leds and somehow I fumble fingered it so now none of the interior lights work. Any suggestions? :banghead:

1. Pull them all out again.
2. Replace blown fuse.
3. Put them all back one at a time with door open; see which one blows fuse.
4. Repair that socket or bulb.
5. Replace fuse again.
 

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Discussion Starter #5
Gee, thanks jimpal! Thanks for the replies Napi and johnre!
 

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2007 2.5 L Obsidian Black Outback XTL
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LED bulbs are polarity sensitive. If you plug one in backwards it presents an electrical short to the car and it will pop a fuse. The bulb fixtures do not tell you what side is positive or negative and on some bulbs you can get them flipped around.
 

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'15 Outback 2.5i Premium
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LED bulbs are polarity sensitive. If you plug one in backwards it presents an electrical short to the car and it will pop a fuse. The bulb fixtures do not tell you what side is positive or negative and on some bulbs you can get them flipped around.
I don't think that's right. If you wire an LED backwards, it won't work, but it won't hurt anything either, since it acts like a reverse-biased diode (because that's what it is) it won't allow electric current to flow through it at all. On the other hand, forward-biased LEDs have very low resistance, so they need a resistor in series with the diode to limit the current or they will burn out, blow a fuse, or possibly both.

I think most of the LED replacements for automotive bulbs come with the limiting resistor (sometimes called a ballast resistor) built in, but perhaps some don't, in which case you probably will blow a fuse.
 

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2016 Outback Premium 2.5 CVT w/EyeSight+SRVD
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If you wire an LED backwards, it won't work, but it won't hurt anything either, since it acts like a reverse-biased diode (because that's what it is) it won't allow electric current to flow through it at all.
Maybe, maybe not. I've been designing with LEDs since ~1973, and some of them have a pretty low reverse breakdown voltage ratings. Besides a ballast resistor, some LEDs also include a reverse-polarity switching diode in parallel to protect the LED. When I was designing high-reliability circuits, I usually included a discrete protective diode even if the LED was expected to have one onboard. This was back when LEDs were about $2 apiece, and a low-power switching diode (e.g. 1N914 or 1N4148) added less than 5 cents to the unit manufacturing cost.

"Anything worth doing, is worth overdoing."
 

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The red LEDs I got for my puddle lights may go one better. They seem to have something like a bridge rectifier in the package so it will work regardless of the polarity. Either that, or I was extremely lucky and managed to plug both of them into the sockets correctly the first time. What are the odds of that happening... something like 0% given that Murphy's Law is in full effect?
 
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