Reference PDF, 33.2 KB, for the 2SJ590LS, indexed in the schematic category. Under JIS naming, 2SJ marks a P-channel FET, so the document is expected to hold electrical characteristics and a package drawing rather than a circuit diagram. The LS suffix denotes a variant that the file name does not define, so make sure the installed part carries the same full code. Technicians use such data to verify pins, voltage and current limits and to choose an equivalent replacement.
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.