Archive for an S400CA main board at revision 3.1, a model name matching the ASUS VivoBook S400CA, although the file itself states no brand. The contents are not listed, so it may hold a schematic, a boardview or both. Check the revision printed on the PCB matches 3.1 before relying on values. Extract with 7-Zip or WinRAR, then use the material to trace power rails, check the charger and standby logic, and locate components behind boot or power faults.
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 @alischematics. 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.
7-ZipWinRARThe Unarchiver (macOS)