If you think it has booted, and the problem is a dark screen......
I make that guess based on led behavior, might be some other problem....
Remove card, mount on some other (linux) computer
cd card/root
edit/ make a file called "bright" (probably need sudo/su)
----------------------
#/usr/bin/bash
cd /sys/class/backlight/edp-backlight
echo 3200 >brightness
--------------------
sudo chmod 777 bright
boot with card, ctr-alt-F2, do it twice, wait until sure is booted
All this is blind, type carefully
login as root,, ./bright,, alt-F1
Then do same to emmc if necessary (edit booted from SD)
Sometimes the fn-F2 does not work, for sure does not work in vt
This forces adequate brightness, not sure why it persists with another (different) boot
I make that guess based on led behavior, might be some other problem....
Remove card, mount on some other (linux) computer
cd card/root
edit/ make a file called "bright" (probably need sudo/su)
----------------------
#/usr/bin/bash
cd /sys/class/backlight/edp-backlight
echo 3200 >brightness
--------------------
sudo chmod 777 bright
boot with card, ctr-alt-F2, do it twice, wait until sure is booted
All this is blind, type carefully
login as root,, ./bright,, alt-F1
Then do same to emmc if necessary (edit booted from SD)
Sometimes the fn-F2 does not work, for sure does not work in vt
This forces adequate brightness, not sure why it persists with another (different) boot
