820-00850-A error at every first boot

[mbcontrol]

I'm working on a 820-00850-A from a A1989 with liquid damage.
I have a question about booting the naked logicboard (only charger with ext.HDMI)

At every first boot it comes this error-message:
"Your computer restarted because of a problem. Press any Key or wait a few seconds to continue."

After a view seconds it boots without error into the login mask.
When i restart from the login mask it boots also again without error message.
When i unplug the charger, the next boot is with error message.
Is this normal - booting this board naked? Or do i have an issue?

 

[2informaticos]

You should see what happens if good battery is connected.

 

[mbcontrol]

Same behavior with good battery - tested with two known good batteries.
I also noticed that the touchbar doesn't work - at least it doesn't show anything when booting or in the login screen. Normally it should show something in the login screen, shouldn't it? We have no password for login.

 

[2informaticos]

Log into macOS, turn off the machine from software and see what happens when turn it on from power button next.
Do not disconnect the battery.

 

[mbcontrol]

I did get the password from the customer. Login into macOS and turn off from software works fine -> no error-message anymore.
So what do you think - there is no issue? Because i can't remember having such a message before.

 

[2informaticos]

Looks good for me...