Yes, same message, using the normal power button or the novo N without holding it, will show it for a sec and turn off.
holding novo will show it for 20 sec and then try to boot or asking for boot device

https://drive.google.com/file/d/1pdT...ew?usp=sharing

I have rewrite a new bios (two chips) and also rewrite the EC image using i2c with SUCCESSOR
My opinion is that the fact that the laptop working while the novo button is pressed (or shorted) maybe means it is not related to bios or EC firmware.
what do you think?...

On the power button i see 3.26v and go to zero when button pressed

just to make the current status clear: when i connect the laptop to AC without battery, the KB light and caps lock light is on, after a minute the laptop is going down and back up (probably it is the bios init process), when it turns on i can see the lenovo screen with some message that it is "finishing update do not power off" and immediately it shuts down.

when it is in this bios init process (without pressing the novo N button) i see the voltage on the power button fluctuating

...

mon2 i found out tha if i connect the daughter board the chargere is getting to 20v but the laptop powers on and shutting down
i found that if i press the SW1 whih is the novo n switch on the board the laptop turns on but if i stop holding the laptop shuts down, any advise?...

Hi,

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due to a vacation i will update here only in the week after next week