> By "that mode", do you mean "1.5A @ 5V" permitted by BC
Neither - OP means devices with missing CC resistors which will fail to charge with a compliant PD source. (The A-to-C cable works because it provides 5V Vbus unconditionally.)
The A-to-C cable often does not work because the resistors are supposed to be in there.
So if you are having complete charge failures, try a different cable.
The A-to-C cable often does not work because the resistors are supposed to be in there.
So if you are having complete charge failures, try a different cable.