Schematic PDF labelled p7, the first and largest file of a numbered set at 1.21 MB. The name gives no brand or full model name, so verify the device from the title block before using it. Being larger than the other parts, it likely contains most of the circuit diagrams, letting a technician trace power rails, locate the PMIC and charging circuit, and follow signals to the display and connectors when diagnosing no-power or no-charge faults. It opens in any standard PDF viewer.
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 @mobileshematic. 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.