The ADV2 BMS uses temperature sensors T6…T11 to inform the user about errors. Note that not all errors are actual errors, they might just signal end of charging or your battery being low.
v6.05 VESC Tool (Mobile App) Temp Sensors:
Temp sensor logic
T1: GP3 (temperature of the BMS)
T2: n/a - just ignore
T3: another BMS temperature variant
T4: Pack / Cell Temp A
T5: Pack / Cell Temp B
Note that both temperature sensors are located in the rear pack, none are in the front pack.
Here are the error codes, shown as 99deg temperature:
T6: Overvoltage protection (aka charging ended)
T7: Undervoltage protection (triggered way too early, if any cell dips below 3.3V)
T8: Discharge overcurrent protection
T9: Charge overcurrent protection (should be impossible to hit)
T10: Over temperature protection
T11: Under temperature protection
Don’t get fooled by the word protection, that’s just how they phrased it. None of them affect riding except overcurrent protection will cut power (above 110 battery amps for several seconds)
Note: on the PC app T2/T3 don’t exist so everything shifts down by two, so the errors are passed in T4…T9