The 3LP02SP part is documented in this 41.9 KB PDF, catalogued under schematics. The name gives only the component code; companion files 3LP02N and 3LP02M share the 3LP02 base, so the SP suffix most likely indicates a package variant. A technician consults such a datasheet for lead assignment, electrical ratings and outline dimensions when swapping a small discrete transistor. Open it in any PDF reader, and verify the footprint and marking on the board match before fitting a replacement.
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.