I have 2 powerbanks that cannot be charged by USB-C port when at 0%. The signaling circuitry simply doesn't work. No idea who designed this. It is silly beyond belief. I have to charge it with normal 5V A-to-C cable for 30 seconds, then unplug, then all the PD stuff will start working and I can fastcharge it with USB-C port again. I'm screwed without A-to-C cable.
Holy shit. This explains why my Anbernic 406v is so weird. If I drain the battery too much, it won't let me charge with anything except with a normal 5v USB A to C cable and the USB-C cable that I use to charge it while it's on does nothing. It makes so much sense now.
This (and the GP) are because your device supports some sort of fast charge USB-PD negotiation, but does not support what is known as “dead battery mode”. Basically, dead battery mode enables those pull down resistors by default (when no power is applied) so you can get 5V to the system, where eventually it would charge up and the chip that can do PD negotiation will be powered. Usually this is done simply by having the negotiation chip default to pull down resistors internally when unpowered.
I have 2 powerbanks that cannot be charged by USB-C port when at 0%. The signaling circuitry simply doesn't work. No idea who designed this. It is silly beyond belief. I have to charge it with normal 5V A-to-C cable for 30 seconds, then unplug, then all the PD stuff will start working and I can fastcharge it with USB-C port again. I'm screwed without A-to-C cable.