Indexed as a schematic, the 180 KB PDF named 1G1-1G7 points to a numbered series of parts, most likely a rectifier diode family where the digits step through voltage grades. No device or board number is stated in the name. A document like this lets a technician compare repetitive reverse voltage and forward current across the range and pick a grade that meets or exceeds the failed part. Read it with any PDF viewer and confirm the package outline matches the footprint on the PCB.
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.