PDF document of about 4.3 MB titled as dock tests, numbered as section 6 of a larger set. The name does not state which device or brand it belongs to, so its scope can only be judged by opening it. Files of this kind usually describe test procedures for a docking or charging connector, listing measurements and expected values that help confirm whether the port, its flex or the related circuitry is faulty. Check that the model referenced inside matches the unit on your bench before following the steps.
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 @esquemaseletricos. 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.