Samsung Galaxy J4 model J400 electrical schematic in an 8.67 MB ZIP archive, E.E standing for the Portuguese esquema elétrico. Once extracted, the diagrams let a technician follow battery and PMIC supply lines, check charging and USB circuitry, and read connector pinouts for the display and sub-board. Searching the pages by component designator speeds up locating a shorted capacitor. Check that the device is really a J400 variant, because the J4 Plus and J4 Core are built on different 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 @esquemaseletricos. Enginerys does not host this file.
How to open a .zip file
Compressed archive that every operating system opens without extra software.