Official schematics for the LA-C781P are often found on technical forums and archives:
The specific the laptop is presenting (e.g., blinking charging LED, looping fan, absolute dead state). lac781p schematic top
To locate problems efficiently without consulting a full layout printout for hours, trace these specific hardware locations on the top side of the board: Official schematics for the LA-C781P are often found
SPI Flash ROM (storing both system BIOS and EC firmware) blinking charging LED
A low-ohm resistor crucial for the charging circuit to measure battery current. B. Processor and Memory (APU)