Laptop motherboard power supply. How is the launch?

Question

Electronics

I'm a beginner, don't throw slippers pliz)
Compal LA 6552 P R board. 1
On this board, when powered by a battery, the power rooms rise only after pressing the power button. And when powered by an adapter, they appear before turning on. In the diagram we see that the button is powered by power 3V. Then it turns out that the laptop from the battery should not start at all, because for the button to work, a 3V duty room is needed, and it will appear only after pressing it. What am I not getting? Explain, please. What is the button powered by when the adapter is off?

Answer 1

3V alw means that it should always be present. Look at this word in the table of modes, at the end of the album.
If it still should not be (according to the table) when powered by a battery, then you need to trace the presence of a pull-up on the 51ON # line and, maybe, on the On / OffBtn # line.
PS Alw , usually - not power. The amperes indicated in the diagram are more typical for a "normal" power supply, and the line with these amperes has a "p" at the end of the name.
How old is the device?