Service schematic in PDF form for the Samsung SM-J250F, the Galaxy J2 Pro class handset, at 1.88 MB the larger of two copies circulating under the same model code. The name gives no board revision or page range, so compare it with the smaller companion file to see which sections each contains. Technicians use such diagrams to follow battery and PMIC rails, trace charging, display and audio paths, and identify components when hunting a short. Any PDF reader opens it; confirm the model code on the phone label matches before relying on 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 @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.