Lenovo Legion Y540 schematic for board NM-C372, revision 2.0, a 2.82 MB PDF. NM-prefixed numbers follow the scheme used by LCFC, Lenovo's Compal joint-venture design house. The diagram covers power circuits, charger, CPU and GPU rails, and interface signals, which helps with tracing no-power and short faults. A related NM-C371 boardview exists for locating parts. Check the board number and revision on your PCB, since Y540 variants may use differing boards.
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 @cynetitsolution. Enginerys does not host this file.
How to open a .pdf file
The standard format for schematics, block diagrams, power-sequence charts and service manuals.
Any PDF readerSumatraPDFFirefox / ChromeFlexBV (links PDF to boardview)