Archive for Apple logic board 820-2327, 1.35 MB in RAR format, with no revision or content details in the name. A package of this size usually contains a schematic PDF. Check the PCB for the same 820 number and look up its revision before relying on values or reference designators. Technicians use such drawings to follow power from the input through each converter, verify standby and main rails, locate test points and find the component causing a short or a failure to boot.
The button opens the matching file on RM Schematics, or a source page if it is not catalogued there yet. The original attachment is from @Mac_Shematic_Santale. Enginerys does not host this file.
How to open a .rar file
Compressed archive — the usual wrapper for a schematic + boardview pair or a BIOS + EC set.