Mac shuts off after 20-60 sec (Fan full speed)

[Thedog]

Macbook unibody (2012) shuts off after aprox 20-60 seconds. When you start it the fan runs at full speed and it takes between 5 to 20 seconds before you see the grey window and then it shuts off.

I've tried these things:

• Boot to Internet recovery
• Boot to USB recovery (install media)
• Boot in Safemode
• PRAM Reset
• SMC Reset (Although I did not see the light change on the power adapter)
• New Ram
• Different harddrive
• Unplugin the actual battery and plugin it in again

I've run an extended hardware test and it showed no errors! And when I run the actual hardware test the system stays on for over 1 hour with the fan running at full speed.

Another thing I noticed is that the "o" key seems to have mulfunctioned, I thought the client spilled something on the computer but he assured me he has not.

Any ideas on this? Im mostly confused to why it doesn't shut off during hardware test..

Example video when trying to boot to USB-installer:
https://www.dropbox.com/s/ugbc58itx7oj944/IMG_3339.mov?dl=0

The sound of the fan is difficult to hear but it really runs at the fastest Ive heard...

 

[Bizybone]

Try disconnecting the HDD and see if it boot's to your USB installer.

 

[Markverhyden]

Try leaving the battery out for some time, like an hour. Then try a SMC reset. But, to be honest, it sounds like the logicboard is toast.

 

[mlcomputers]

Try leaving the battery out for some time, like an hour. Then try a SMC reset. But, to be honest, it sounds like the logicboard is toast.

+1 on the logic board more than likely being the problem. I have had few macs with similar symptoms and it has been the logic board. Often not worth repairing due to cost of replacement board.

 

[Thedog]

Pulling out the harddrive made no change. The computer is still under warranty but since the client is in a hurry we got him a new one and will leave this one to Apple.

The selling point of Apples "Using a hardware made for the OS" is becoming more obscure every day I think. Just today I had another MBP 15" 2011 which seems to be affected by some AMD graphics issue that has extended warranty. The iMac has a lot of bad batches as well

 

[theitsage]

The MBP 13" 2012 has a lot of issues even though it's the last of unibody non-retina. If you haven't tried it, boot the laptop with only one RAM stick in the bottom slot (top slot when open).

 

[Greg Kristy]

Check , just in case, if this is the problem:
https://www.technibble.com/forums/t...-starts-powering-up-and-thencuts-power.76252/
(referring to my proposed solution at the end of the thread

 

[GTP]

@Greg Kristy
Thread is over 2 years old...Do you think they may have fixed it by now?

 

[Greg Kristy]

Haha well executed. I might start glancing at the date field occasionally now.