Resistance-to-ground chart for iPhone 7 Plus connector J4502, which the Chinese title identifies as the display and touch socket, packed in a 7.08 MB PDF. Each pin has a reference value, so a technician can measure the logic board and quickly spot a shorted or open line causing no image, no backlight or dead touch. Open it in any PDF viewer. Values depend on meter and mode, so use them alongside a known good board rather than as absolute figures.
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 @uzb4422. 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.
Any PDF readerSumatraPDFFirefox / ChromeFlexBV (links PDF to boardview)