Datasheet for the 1N5059 diode as a 52.4 KB PDF, filed in the schematic category though it is a part specification sheet. It should list reverse voltage, forward current, surge capability and mechanical outline, the figures needed when a rectifier in a power section shows a short or open junction. Open it with any PDF reader. Before replacing, compare the package and lead pitch with the board, pick a substitute with equal or greater ratings, and orient it by the cathode band shown in the drawing.
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.