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Discussion Starter #1
Hi, I'm looking for some much-needed help. Earlier, I was trying to install my LEDs and it was going fine until I got to the vanity mirrors. I didn't know how to turn it off so I just took the bulb out while it was still on and put the LEDs on right after (it didn't work). After that, I turned the car on and everything was reset (mpg, trip mileage, etc). What's worse is that my audio no longer works. I cannot turn on the radio or listen to CDs or anything. And I can't lock/unlock the doors using the buttons on the key. What can I do to fix these problems? Any help would be greatly appreciated!
 

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Unplug the battery to turn the lights off...u probably short circuited it
 

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If the vanity LED's aren't working they are probably in backwards, they only work one way. ( they are polarity sensitive)
BUT....
Now for the bad part....sounds like you may have fried the BCU, which controls all the lighting on the car among other things ( door locks) the vanity lamps are not protected by a fuse, at least I have not seen a fuse called out for it but it may be tied to the map light fuse....but the loss of other things makes me think it may be the BCU/ Body Controll Unit ( google BCU)
I would take all the leds out and put back the factory lamps and bring it in for repair under warranty. Don't tell them about what you did just say they suddenly stopped working!
Good Luck!
 

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If the vanity LED's aren't working they are probably in backwards, they only work one way. ( they are polarity sensitive)
BUT....
Now for the bad part....sounds like you may have fried the BCU, which controls all the lighting on the car among other things ( door locks) the vanity lamps are not protected by a fuse, at least I have not seen a fuse called out for it but it may be tied to the map light fuse....but the loss of other things makes me think it may be the BCU/ Body Controll Unit ( google BCU)
I would take all the leds out and put back the factory lamps and bring it in for repair under warranty. Don't tell them about what you did just say they suddenly stopped working!
Good Luck!
Do this i may or may not have cooked my BCU with LED lights, so I took it in and it turns out it was cooked. its a $500 CAD part, so return to stock everythign and send it in.
 

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Discussion Starter #6
I took it in to the dealership today and it turned out there was a blown fuse. Nothing wrong with the BCU (fortunately!) So $1.69 and 2 minutes later, everything worked again! Thanks for the help though!
 

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Lucky break!

Keep in mind, it's a good rule of thumb to pull the battery before working on anything dealing with the car's electrical system.
 

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2012 Mazda 3 Skyactiv
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When I installed the LED lights, I found that if you do not open the "sliding door" all the way, then the light does not turn on. I made sure mine where off simply because the bulbs were really hot when they were on.
 
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