Named 30WQ04FN and filed as a schematic, this 131 KB PDF most likely holds a component datasheet for a Schottky-type rectifier, based on the part-number format. No board, laptop or revision appears in the name. Such a datasheet supports component-level repair: checking polarity, forward voltage and surge current when a rectifier near the power input reads shorted. Before substituting, compare the marking and package drawing with the part on the PCB and confirm the voltage code matches or exceeds the original.
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 @cyberlanelectonik. 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.