Small 27.3 KB PDF for part 5LN02C, listed as a schematic though it is evidently a discrete-device datasheet. The name holds only the part code; LN appears to indicate an N-channel MOSFET and C a package type within this series. Consult it to confirm terminal layout and absolute maximum ratings, and to compare threshold and on-resistance with a proposed substitute. Verify the footprint and component marking on the board first, since sister parts differ mainly by case.
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.