A small 68.0 KB PDF whose name holds only the component code 1SS337, with no brand, model or board number given. 1SS is the Japanese JIS designation for small-signal diodes, a range most often associated with Toshiba, so expect a datasheet rather than a full circuit diagram. It serves for checking pin configuration, absolute maximum ratings and package dimensions when a diode fails on a logic or power line. Before soldering in a substitute, compare the marking code and footprint with the original part.
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.