I have a boot issue with a system consisting of
- Raspberry Pi 4 B+
- Raspbian 10 (buster)
- 7" capacitive touch display (the "official" one) and a
- custom shield that pulls BCM17 (pin 11) high, when external 12V present.
Everything works fine with BCM17 when the system has booted. I can read the pin and it reflects the status of my external 12V.
But when I first apply 12V and then the Pi supply voltage, the system won't boot.