Electrical schematic for the LG D337, an L Prime series phone, supplied as a large 53.7 MB PDF. The size suggests high-resolution pages, possibly including board layout views alongside circuit diagrams. A technician uses it to trace supply rails from the battery and PMIC, verify charging and USB lines and identify connector pinouts. Zoom into the pages for designators and test points. Make sure the model on the phone label matches D337 before relying on values, since related LG models use other 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 .pdf file
The standard format for schematics, block diagrams, power-sequence charts and service manuals.