Sorry for resurrecting old thread, but I think it’s better to keep related topics together.
Recently I have similar problems with USB-PD. Normal charger (24V, with barrel-jack) works, and OLED shows around -1.4A when charging. When it’s connected, red LED D8 shines; when batteries are full, D9 also shines, but it stays off during charging.
But when I connect AdaFruit 20V cable, MNT Reform is not charging. I tried 2 different cables, so I treat failure of them as low probable. OLED shows no external power, and 0.0A. D8 initially is on, but after few seconds starts blinking. I tried to analyze firmware, but haven’t found code responsible for LEDs. Not sure if it’s there, or if they are managed by hardware.
What makes it strange: I tried 15V cable and it was working! It started charging, LEDs were on. OLED was showing -0.5A; lower than with normal charger, but IMO still usable.
Don’t know yet what to think about that. I’ll be trying different combinations and should let you know if find something interesting. If someone has tips regarding firmware, please share. At the same time, this is not project with high priority, so I’m taking care of it in free time.