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Model A1418 / Late 2012 / 2.7 & 2.9 GHz Core i5 or 3.1 GHz Core i7 Processor

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Can't boot, no LED indicator lights on logic board

Hi there

I wonder if anyone can offer any advice.

My friends’ computer stopped booting so he gave it to me. It’s a nice computer that I would like to repair and give to my mother.

Pressing the power button gives no response at all.

I removed the screen and noticed there were no LED indicators alight on the logic board, so assuming it was the PSU I ordered a replacement. I also ordered a PCIe Blade SSD as the logic board allowed it. I removed the existing HDD and returned it to my friend.

After the new PSU arrived, I installed it with the new SSD and put it back together however the machine still has the same issue (along with no LED indicators).

So I tested the DC voltage on the new PSU and it noticed it was giving me a zero reading (must be dodgy so I will return it).

I then installed the old PSU and I am actually receiving an 11.80v reading on 3 pins. So my question is, in anyone else’s experience, do you think this is a dodgy PSU (at 11.80v) or would it seem like the logic board is the culprit?

Any advice is greatly appreciated!

Cheers

Luke

Answer this question I have this problem too

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Most Helpful Answer

PSU problems, period. Most bad PSU will still give you a green light on LED#1 and you are not getting that far.

Even though you probably can get cheaper parts, I get mine from ifixit because they carry a lifetime warranty, and I only want to do the repair once as my time is more valuable to me than doing a repair all over because I got cheap part.

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2 Comments:

Thanks so much for your response. I took your advice and ordered a new PSU.

I've installed it and unfortunately, I still have the same problem. The computer does not boot and no LED indicators light up on the logic board.

When I check the voltage on the pins that are connected to the motherboard I can see 12v so the PSU is supplying power.

I'm wondering if in this case, it is the logic board that has kicked the bucket...

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@lanzalf Logicboard failures are very very rare but if at least the #1 LED is not lit (indicating at least some power going to the logic board) (This LED is usually lit even with a failing power supply) it does appear you have a bad logic board. I have never even see a bad logic board on this series. Yes, bad GPU and bad CPU but not the board. Ask your friend if anyone ever got into it and attempted to work on it. @danj what is your opinion on this one?

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Luke L will be eternally grateful.
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