The device can permanently disable the use of the battery pack in case of a significant failure. The permanent failure checks, except for IFC and DFW, can be enabled or disabled individually by setting the appropriate bit in Settings:Enabled PF A, Settings:Enabled PF B, Settings:Enabled PF C, and Settings:Enabled PF D. All permanent failure checks, except for IFC and DFW, are disabled until ManufacturingStatus()[PF] is set. When any PFStatus() bit is set, the device enters PERMANENT FAIL mode and the following actions are taken in sequence:
- Precharge, charge, and discharge FETs are turned off.
- OperationStatus()[PF] = 1, [XCHG] = 1, [XDSG] = 1
- The following SBS data is changed: BatteryStatus()[TCA] = 1, BatteryStatus()[TDA] = 1, ChargingCurrent() = 0, and ChargingVoltage() = 0.
- A backup of the internal AFE hardware registers are written to data flash under PF Status: AFE Regs: OCC, OCD, , Short Circuit Discharge, Current Dischareg Wake, Current Charge Wake, OCC 1 Delay 2, OCC 1 Delay 1, OCD 1 Delay 2, OCD 1 Delay 1,Short Circuit Discharge Delay, Over Temperature Delay, OCD Wake Delay 2, OCD Wake Delay 1, OCC Wake Delay 2, OCC Wake Delay 1.
- The black box data of the last three SafetyStatus() changes leading up to PF with the time difference is written into the black box data flash along with the 1stPFStatus() value.
- The following SBS values are preserved in data flash for failure analysis:
- SafetyAlert()
- SafetyStatus()
- PFAlert()
- PFStatus()
- OperationStatus()
- ChargingStatus()
- GaugingStatus()
- Voltages in DAStatus1()
- Current()
- TSINT, and TS1from DAStatus2()
- Cell DOD0 and passed charge
- Data flash writing is disabled (except to store subsequent PFStatus() flags).
Note:
While the device is in PERMANENT FAIL mode, any new SafetyAlert(), SafetyStatus(), PFAlert(), and PFStatus() flags that are set are added to the permanent fail log. In addition, new PFStatus() flags are recorded in the Black Box Recorder 2nd and 3rd PF Status entries.