No signs of power - checked pretty much everything!

This is regarding a laptop of a friend I am trying to fix. She allegedly droped it around 20cm straight onto the base on carpet. Everything was fine but when she came back to it a few minutes later it was off, the charging light not lit and did not respond to pressing the power button (which is unfortunately on the keyboard and not a separate button). And after quite some troubleshooting this is still all it does!

Here is a list of things I tried:

- checking power socket, fuse and ultimately open circuit voltage of the PSU, which is well within range (19.4V actual open circuit, specified 19V)

- checking CMOS battery, standard CR2032, to make sure it didn't disconnect due to the drop

- replacing said CMOS battery even though the old one had a reasonable open circuit voltage of 3.1V and short circuit current (for 1s) of multiple hundred milliamps

- removing and reseating RAM

- removing and reseating battery

- checking battery cell voltages, interestingly I could not measure any voltage on the connector. Might be a dead battery or the protection circuit just disconnects the output when the battery is removed from the system

- disconnecting PSU and the (stupidly integrated) battery, pressing the (keyboard) power button for 30s, then reconnecting everything

- doing above but with the on-board power button (which doesn't actually exist, it's only the board footprint of a micro switch which isn't populated but marked PW1. "Pressed" by connecting smd pads)

- making sure the case cutoff switch (which exists for some unknown reasons) is actually engaged when the case is closed

The only thing that I could think of which I haven't tried is doing the 30s power switch procedure while the case cutoff switch is engaged since I only tried it with the case open and the switch not pressed. Unfortunately I don't have a multimeter around (university halls) thus I can not check the voltage on battery/board test points while the battery is connected.

Any idea what to check or any other advice would be greatly appreciated!

Answer this question I have this problem too

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