Schematic for the IBM ThinkPad A31, a 1.00 MB PDF whose name gives only the model. No board number or revision is mentioned, so compare the PCB markings with the drawings before use. Such documents serve component-level repair, letting you trace each voltage rail back to its regulator, check signal routing between major chips and find what pulls a line to ground. Searching net names in a PDF viewer speeds up diagnosis. A31 boards may vary by configuration, so check the video section carefully.
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.