Circuit diagram in PDF for a board identified as SN3 with the code name SHINAI-3, a 1.16 MB file. The name gives no laptop brand or revision beyond that project label, so check the title block inside to confirm the exact model. Schematics of this kind are used to follow power rails from the adapter input to the CPU and memory regulators, identify components on a shorted net and locate test points. Before measuring against it, make sure the code name on the PCB matches.
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 @smschematics. 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.