Listed as a schematic, this 73.3 KB PDF has the name 15cljq150, a code in the style of International Rectifier or Vishay Schottky rectifiers. It most likely holds the component datasheet, including package type, pin assignment, reverse voltage and forward current limits. The data helps a technician confirm a shorted or leaky diode found with a meter and choose an equivalent with sufficient margin. A similar 15cljq045 file exists in the set, so read the voltage grade on the part carefully.
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.