For the 2SC5703 there is this 167 KB PDF, catalogued as a schematic but almost certainly a part datasheet, since 2SC denotes an NPN bipolar transistor in the JIS system. The name lists nothing else. Use it to look up pinout, breakdown voltage, collector current, dissipation and gain range during fault finding. When choosing a substitute, keep ratings equal or higher and check that the package and lead order match the PCB footprint exactly.
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.
Any PDF readerSumatraPDFFirefox / ChromeFlexBV (links PDF to boardview)