A1502 820-4924 stuck in boot loop with kernel panic

sekidata

Member
This 2015 Pro chimes, begins booting, kernel panics, tries to restart.
I've already replaced the EFI (U6100) with a clean ME region. Also replaced U6101 and checked the EFI termination resistors.

What's keeping this board from loading the BIOS?
 

2informaticos

Administrator
Staff member
If chimes, PCH accesses BIOS and board boots.

Tried USB macOS?
You can also test with Windows Live, or Linux.

Still panics in safe mode?
 

sekidata

Member
Still panics in safe mode and with external USB drive using macOS. The only thing that does work is running ubuntu from USB.
 

sekidata

Member
I just found an old SSD with High Sierra on it, and the machine boots fine with this OS. However, it randomly kernel panics later during use (report attached).

Running Apple Diagnostics stalls in the early stages of testing.

Failing CPU or RAM on this machine?
 

Attachments

  • Problem report.pdf
    37.4 KB · Views: 0

sekidata

Member
I also noticed that there is a discrepancy between the amount of RAM printed on the logic board (8GB) and that reported by System Information (16GB). No idea how that is possible... ? Shouldn't a PRAM reset correct this?
 

2informaticos

Administrator
Staff member
Check the capacity of your RAM chips and guess te real amount.
You may find it in Gb, not GB, then should divide by 8; 1GB=8Gb.
See if you have 2GB, or 4GB chips.
 
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