Indexed as a schematic, this 201 KB PDF is named 81CNQ045A, a part code following International Rectifier dual Schottky diode conventions, with an A suffix for a variant. It is best treated as a component datasheet. Repair technicians use such sheets to check which pins form the common terminal, what forward voltage to expect on a diode test and which ratings an alternative part must meet. Read the marking on the device carefully, since suffix variants can differ in package or specification.
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.
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The standard format for schematics, block diagrams, power-sequence charts and service manuals.