Black screen on Mac air…Will not charge..help

See this article.

If your Mac battery won’t charge - Apple Support

"Black screen on Mac air…Will not charge..help: Why does my air Mac 13 inch not take a charge anymore"

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What I've tried, and it seamlessly works...

Hold Down these at boot:

• [power button + F9]
• [power button + option + F9]
• [power button + option + fn + shift + F9]

TheLittles wrote:

"Black screen on Mac air…Will not charge..help: Why does my air Mac 13 inch not take a charge anymore"

-------

What I've tried, and it seamlessly works...

Hold Down these at boot:

[power button + F9• ]

[power button + option + F9• ]

[power button + option + fn + shift + F9• ]

What are these supposed to do? I've never heard of this key combination before. Do you have any references for them?

Also, are these special key combos for an Intel or Apple Silicon Mac?