Full schematic for the Huawei G525 smartphone, provided as a 585 KB PDF. The name lists no board revision, so compare the circuit labels with your phone's mainboard. For phone repair this kind of document shows the PMIC outputs, battery and charging path, display and camera connector pinouts, and the signal lines between processor and peripherals. Technicians use it to check voltages at connectors, trace a short on a supply line, and identify the role of an unmarked component. Any PDF reader opens it.
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 @schematic_mobiles. 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.