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Top left gold plated power cables?

MacBook doesn't power up anymore after the battery ran out of juice. The light of the MagSafe adapter doesn't give an indicator light either. Two adapters tested. SMC reset done.

Figured it would be the MagSafe DC-in board. Just replaced it. No luck. No light either.

Now about two years before I swapped the Super Drive for an SSD kit, and damaged a gold plated cable, of which the connector is labelled J2. There are 3 of those same connectors next to each other in the left top corner. Presumable the power cable running through the hinge of the display?

Photos of the J2 cable in the left top corner

I was thinking it might be a short within the cable (like in coax), but I am not sure if it is this kind of cable. Could be the connection is damaged all together, though it did work fine for two years.

Can anyone clarify a bit more on the matter? Or any ideas what else could be the problem?

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The cables in your photo aren't power cables; they're the antennas for Airport and Bluetooth. They attach to the card at the lower right of your first photo, and then run through the display clutch hinge into the display assembly. A flat ribbon cable then connects the AP/BT card to the logic board.

MacBook Pro 15" Unibody Mid 2012 AirPort/Bluetooth Board Replacement

MacBook Pro 15" Unibody Mid 2012 AirPort/Bluetooth Cable Replacement

I recently replaced the AP/BT card in my 2012 MacBook Air, because I'd smushed a coax connector on the card. What I discovered is that the wireless still worked, but the range and stability was greatly reduced. It looks to me like the connector on the longer cable in your photo was compressed; had you noticed reduced WiFi/BT functionality before the computer failed? If not, I wouldn't worry about that area.

In many laptop models, the computer won't start up if the battery's completely dead, even if you're connected to a charger. There are a few things you can try:

  1. Make sure the computer is powered off (check the Caps Lock key to see if it lights up, or check the sleep light on the front edge of the computer; the charger light on the MagSafe connector may not light up if the charger has been damaged). Then plug the computer into AC, and leave it alone for an extended period of time - 24 hours, say. If the charge system is working at all, you may get enough juice into the battery to be able to get the MBP to sound the post chime.
  2. A quicker way to isolate a battery problem is to open the computer, disconnect the battery from the logic board, then try powering up from AC only. If the chime sounds and the computer boots, then the problem is specific to the battery. The computer is four years old; the battery may be completely worn out by now - replace it.

MacBook Pro 15" Unibody Mid 2012 Battery Replacement

MacBook Pro 15" Unibody (Early 2011 through Mid 2012) Replacement Battery

It's possible the replacement DC-in board was a deadster; where did you get it from? And did you do an SMC reset after you installed the replacement board?

MacBook Pro 15" Unibody (Early 2011 through Mid 2012) Replacement Battery Image

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I did the SMC reset.

yesterday i left it charging and i am at work today while it is still charging.

If i have a bit of spare time tomorrow i will try to boot the macbook without the battery connected.

The part itself is bought from

It was a refurbished one 'with a lifetime warranty'.

The reason that i didn't think it was a battery problem is because it was charging badly for a while, and when i reconnected the magsafe (sometimes a couple tries where necessary). It would make connection. The last time the macbook was powered on (a while back, say months, put off fixing it for way to long) the magsafe didn't connect at all and the battery slowly but surely dried up.

A friend of mine bought a macbook retina about a year ago and donated me his extra magsafe adapter. Changing magsafe adapters didn't fix my problem so it is my understanding that the problem lies somwhere between the magsafe adapter and the battery.


Didn't had a lot of time past week, which allowed the macbook to 'charge' for about 5 days. when it didn't power up i felt the magsafe adapter and it was completely cold.

Then i tried to remove the battery and start it up without. Tried both chargers but no luck as well.


Sounds to me like the MagSafe DC-in board you swapped in was a dud. I'd contact PowerBookMedic for a return/replacement; they're generally pretty good about that. Replacement parts from iFixit now have a lifetime warranty; return it with an explanation and they'll send you another one. FYI, iFixit currently has used ones for $14.95 and new ones for $24.95.


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