Schematic section in PDF for the handsfree, meaning the headset or wired earphone jack circuit, from an unnamed sectioned set of roughly 4.77 MB pages. No model or board revision appears in the name. The page should show the jack pinout, headset detection line, left and right audio channels and the headset microphone path. It helps when a phone does not detect earphones or stays stuck in headset mode, allowing you to trace each line to the codec. Match the drawing to your device before testing.
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 @phoneSchematics. 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.