PDF reference for the 2SC3665, sized 175 KB, with no device or board information in the name. In Japanese JIS part numbering the 2SC prefix identifies an NPN bipolar transistor, so the contents are likely a component datasheet rather than a circuit drawing. Look for voltage and current ratings, gain groups and the case outline. Before swapping a suspect part, match the pin order shown here with the board footprint and confirm the replacement meets or exceeds every listed rating.
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.