That is the button behind the "emergency reset hole" in the bottom case panel. It's explained in the user manual.
Emergency Reset Hole
Gotta be a punk rock band name, no?
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That is the button behind the "emergency reset hole" in the bottom case panel. It's explained in the user manual.
Emergency Reset Hole
Gotta be a punk rock band name, no?

No luck on the punk rock band, but I thank you for the help with the manual! XD
"i need somebody to touch my emergency reset hole."
No idea what the button is and I found nothing about it in the Hardware Maintenance Manual
https://download.lenovo.com/pccbbs/mobiles_pdf/t480_hmm_en.pdf
The system board has the part id 01YU859
https://pcsupport.lenovo.com/se/sv/parts-lookup?partId=01YU859&subsource=sharelink
Scribd has the schematic of the board, but I'm not technical enough to use it and answer your question.
https://www.scribd.com/document/619356079/Lenovo-ThinkPad-T480-01YR328-NM-B501-rev0-1