This 106 KB PDF carries the part number 2SC5044 and is catalogued as a schematic. Since the 2SC prefix in the Japanese JIS system marks NPN transistors, the content is most probably a datasheet. Nothing else, such as manufacturer or package, is given in the name. Use it to confirm lead assignment, collector-emitter breakdown voltage, collector current and gain before replacement. Small surface-mount versions often carry short marking codes, so cross-check against the sheet.
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.