PDF schematic of 5.39 MB whose name is just an automatic messaging-app document number, so it reveals no brand, model or board number. Open it in a PDF reader and read the title block or page headers to identify the board and revision. Once identified, a schematic like this lets you follow power rails, check the power-on sequence, read component values and trace signals when locating a short. Make sure the board number printed on the PCB matches the document before using its values.
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 @pdf_servicemanual. 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.