Circuit diagram for the K42JR notebook motherboard in PDF format, 2.30 MB. The name holds only the model code, without a revision or board number, so the title block and the PCB markings should be compared. With it you can trace power from the adapter input through charging and DC-DC stages, check standby and main rails, locate the components on a shorted line and follow signal paths between chipset, memory and peripherals. A PDF reader with text search helps locate net names quickly.
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 @schematicslaptop. 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.