Compact 43.6 KB PDF named for the 3N249 and filed as a schematic, although it is almost certainly a component datasheet. Under JEDEC rules the 3N prefix covers registered four-lead semiconductors, and the matching file size with nearby numbers suggests a combined family document. A repair technician would check pin assignment, limiting values and the package outline before testing or replacing the device. Any PDF viewer opens it; confirm the exact grade marked on the board before choosing a substitute.
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.