A PDF of about 88 KB for the 2SK2154, filed under schematics but most likely a component datasheet, since the name is just the part number. Under the Japanese JIS scheme the 2SK prefix marks an N-channel field-effect transistor, usually a power MOSFET in board repair. The name gives no maker or package. Use the sheet to confirm drain-source voltage, current rating, on-resistance and pinout before fitting a replacement. Check the markings on the original part match before trusting the specs.
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.