Your problem requires disassembling your complete laptop to get to the processor chip.
The factory forgot to remove a serial number label placed directly on the processor's heat sink so it causes the processor to get hot and shutdown to prevent damage.
So you disassemble the laptop and remove the motherboard with attached heat sink on the bottom. Don't forget to use ESD tools and strap as you can destroy your motherboard. On a solid surface unscrew the 4 screws that hold the heat sink on the processor and carefully remove it. Clean off any old heat sink paste with a small cloth or paper towel. Rip slightly the serial number label and fold it so that none of it is on the heat sink but just the surrounding processor. Apply new Arctic Silver heat sink paste evenly to the processor pad. Re-attach the heat sink and assemble the laptop in reverse order of your disassembly.
It will work fine after this repair.
This repair was learned and used when my ownToshiba P775 had the same failure.