ASUS K43L service material packed in a 48.5 MB ZIP archive, with the name pointing to board revision 3.1. The listing does not say exactly what is inside, though an archive of this size typically bundles schematics, boardview data or firmware for the model. Unpack it and check each file before working on the board. Make sure the revision printed on your mainboard reads 3.1, because ASUS often changes component placement and power circuitry between revisions of the same model, and a mismatch can send rail tracing in the wrong direction.
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 @azvoltagemap. Enginerys does not host this file.
How to open a .zip file
Compressed archive that every operating system opens without extra software.