Schematic in PDF form for a TCL television board identified in the name as 40-L141H4-PWG1CG, which by its layout appears to be a power supply or combined power board for a 40-inch class set. The file is small at 114 KB, so expect only a few pages. Technicians use such a diagram to follow the primary and secondary sections, locate the PWM controller, check standby and main output voltages and trace a short on a rail. Compare the code silkscreened on the PCB with the one in the drawing before relying on component values.
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 @pdf_servicemanual. 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.