Part 5LN01N is described in this 27.9 KB PDF, placed in the schematic section. The name gives nothing beyond the part code; within this family LN appears to indicate an N-channel MOSFET and the N suffix a specific package. Open it in any PDF reader to check gate, drain and source pins, absolute maximum ratings and threshold voltage during diagnosis. Make sure the package and marking on the board match this document before ordering a replacement or substituting a related variant.
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.