We are experiencing a strangely high FCC, Remaining Capacity and Absolute SOC readings with BA20Z80ADBT-V110. All of a sudden FCC and remaining Capacity jump up to 63259 mAh resulting in Absolute SOC of 1090% while Relative SOC stays at 100%. Looks like 16 bit registers that hold capacity values have 111 instead of 000 in the 3 highest bits. Masking the highet 3 bits, then the number would be around 5900 which is what we expect to see under normal conditions.
We also noticed that RCA (Remaining Capacity Alarm) was set at the same time, while it is programmed to trigger when < 660mAh. According to Technical Reference sluu276 Remaining Capacity is an unsigned integer. Is it possible that it is treated by the BQ20Z80’s firmware as a signed integer and the Remaining Capacity Alarm is set because it thinks the value is “-32492”mAh?
Does anyone know what causes this? How can it be prevented? Is there any way to force this failure so a solution can be tested?