PDF reference sheet for the 2SC3184, filed in the index as a schematic but named after a single part number in the Japanese JIS scheme. The 2SC prefix marks an NPN bipolar transistor, and the body of such parts is usually printed without the leading 2S, so it may read C3184 on the board. At 98.9 KB it most likely holds pinout, package outline and maximum ratings. Use it to confirm lead order before testing junctions with a meter, and match the printed marking before trusting any 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.