SME - HV BATTERY CELL MODULE VOLTAGE FAULTS. When diagnosing with ISTA or ISTA Next, a fault code (detailed below), regarding the cell voltage measurement, is entered in the battery management electronics (SME). ? 21F0C2 - High-voltage battery, cell supervision circuit 1: Voltage measurement (battery cell), line disconnection ? 21F0C3 - High-voltage battery, cell supervision circuit 2: Voltage measurement (battery cell), line disconnection ? 21F0C4 - High-voltage battery, cell supervision circuit 3: Voltage measurement (battery cell), line disconnection ? 21F0C5 - High-voltage battery, cell supervision circuit 4: Voltage measurement (battery cell), line disconnection ? 21F0C6 - High-voltage battery, cell supervision circuit 5: Voltage measurement (battery cell), line disconnection The customer might not have reported the situation as the fault code could have no effect on the vehicle operation. Erroneous fault in the fault memory of the SME, possible fault in a cell supervision circuit (CSC) or a cell module.
