Chosen Solution
Macbook Model A1398 EMC 2512, stop in any startup group, when attempting (D) to diagnose this error (0x8000000000000003, Cannot Load ËFI / Drivers / TestSupport.efi “Also do not continue with Command + R, or Option + Command + R , or normal boot : interrupts the process during initialisation the white line stops and not the continuity
The diagnostics error is caused by Apple messing up the systems EFI! They broke diagnostics! At this point you need to try swapping things to isolate the problem. Do you have access to a bootable external drive? You would need to remove the internal SSD to see if that worked. The next thing is trying a new battery. You may want to let some one who has the gear to test things
