Based on field reports from repair shops, here are the top failures for the LA-D401P platform:
For gaming laptops like the Legion Y520, the GPU (GTX 1050/1060) is a high-failure area. The schematic provides the voltage requirements for the GPU core (VCC_GFXCORE) and memory (VCC_GDDR). If these rails are missing, the schematic helps you trace the controller (e.g., NCP81215) back to its enable pin.
The LA-D401P is a switch-mode power supply (SMPS) board designed by LG. Its primary function is to convert AC mains voltage into the various DC voltages required by the TV's mainboard and the OLED panel itself.