PDF of 208 KB covering the 2SC5550, listed in the index under schematics but by its JIS part code an NPN bipolar transistor, so treat it as a component datasheet. Neighbouring numbers 2SC5548 and 2SC5549 appear in the same collection, which suggests a related family. Repairers use the sheet to verify pin order, absolute maximum values and switching or frequency characteristics before replacing a failed device. The name states no package or manufacturer, so confirm the marking on the original part first.
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.