820-00426-A restarting during boot.

[arash]

The board powers on fine but gets stuck with around 70% on the boot progress bar. The fans also gradually start spinning to a far higher RPM than normal. After a short while, it then simply reboots. Alt + D doesn't show any issues.

Any ideas?

 

[2informaticos]

Try clean ME BIOS first...

 

[arash]

Thank you. We've tried it again with a cleaned ME region and while it did manage to boot into an installation media, the installation of High Sierra took ages. The system now only boots to 90% and stays there indefinitely.

 

[2informaticos]

How did you clean ME region?

 

[arash]

Hi, sorry for the late reply.

We have found a BIOS dump with a clean ME Region and flashed it.

There so far has not been any further progress on the device.

 

[2informaticos]

Don't say from vinafix...
Upload somewhere original BIOS read from your board.
I hope you did backup!
And buy Medusa programmer, if you deal with Apple stuff...

 

[JohnB8812]

Did you try a new battery?