Only the part number 1SS374 is given in the name of this 68.5 KB PDF, so treat it as a component specification rather than a board schematic. The 1SS designation in the Japanese JIS system covers small-signal silicon diodes. Repair use is straightforward: identify the anode and cathode, read the SMD marking code, check the maximum ratings and find an equivalent if the original is unavailable. Open it with a standard PDF reader and match the package outline with the part fitted on the board.
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.