apple hardware test error DEC400

Question

apple hardware test error DEC400

I have a macbook pro 2012

I have an infinite panic kernel problem.

I used an external hdd to access the computer, and I have formatted and installed mojave, but things continue and I can not access the test hardware.

I can not solve this problem and I can not access the test hardware. It's 10 days that you struggle with the kernel panic. today I thought everything was ok. nothing in the whole day. instead this evening again kernel panic.

please help me

MacBook Pro

Posted on Dec 14, 2018 3:16 PM

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Answer 1

Dec 14, 2018 3:37 PM in response to Antonio Demarcus

Dear Antonio ,

Welcome to Apple Discussions .

Well Did you restart holding the D key, for on your Mac AHT ?

That error code is a general failure code of no value.

If you have internet connection try holding the option key + the D key on reboot— to connect with Apple servers.

How to use Apple Diagnostics on your Mac - Apple Support

Regards

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Answer 2

Dec 14, 2018 8:33 PM in response to Antonio Demarcus

Can you successfully boot—download and run the etrecheck utility app

Try a SafeBoot https://support.apple.com/en-us/HT201262

You can also look for kernel panic in the crash logs:

From the Applications/Utilities/Console.app

or from Finder>Go>Go to Folder> copy and paste:

Library/Logs/

https://www.lifewire.com/troubleshoot-mac-os-x-kernel-panics-2260849

If your Mac spontaneously restarts or displays a message that it restarted or shut down because of a problem

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Answer 3

Dec 15, 2018 1:05 PM in response to Allan Jones

finally with a pc I managed to create a usb boot. I'm trying the test and the fans do not want to stop making noise. I think it's a hardware problem, not HDD, nor RAM.

ok

The result of the error

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Answer 4

Allan Jones

Level 9

68,870 points

Dec 14, 2018 5:45 PM in response to Antonio Demarcus

This reference came up quickly in a web search:

https://www.ifixit.com/Answers/View/530196/Hardware+Problem+in+MBP+2012+after+Mojave+install

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apple hardware test error DEC400

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