FLA48200/FLA48300/FLA48500 and LUX-Y low-voltage LiFePO4 batteries (BMS fault code list)
Felicity C08 error code
MOS under-temperature: the BMS MOSFET temperature is below its operating limit.
Likely causes
- Ambient temperature below the battery's operating range
- Battery installed in an unheated or exposed space
- BMS temperature sensing fault
Checks to run, in order
- 1Measure the ambient temperature at the battery
- 2Compare it with the battery's operating range
- 3Check that the battery is not exposed to cold draughts
Fixes
- Warm the installation space to within the battery's range
- Do not charge the battery below 0 °C
- Restart the unit; if the error persists, contact the repair centre
When to escalate
If C08 persists at normal ambient, escalate for BMS temperature-sensor service.
Fix it with the right tools
Check the system around the fault before replacing parts: load, battery bank, PV string and commissioning settings. If you need a second opinion, send the code and your inverter model to our team.
Before you open the inverter
- Isolate both the AC and DC sides, then confirm the display is dead before touching terminals.
- Use insulated tools and one hand where possible. DC arcs do not self-extinguish like AC.
- If you see burnt terminals, swollen cells, leaking electrolyte or a burning smell, stop and escalate instead of resetting the fault.
Questions installers ask
What does Felicity C08 mean?
MOS under-temperature: the BMS MOSFET temperature is below its operating limit.
How do I fix Felicity C08?
Warm the installation space to within the battery's range Do not charge the battery below 0 °C Restart the unit; if the error persists, contact the repair centre
When should I escalate Felicity C08?
If C08 persists at normal ambient, escalate for BMS temperature-sensor service.
Can I reset Felicity C08 myself?
Only after isolating the AC and DC sides and running the checks above. If Felicity C08 returns immediately, stop resetting it and escalate; a repeating fault usually points to a real circuit, battery or hardware problem.
Which models show Felicity C08?
Felicity C08 is documented for FLA48200/FLA48300/FLA48500 and LUX-Y low-voltage LiFePO4 batteries (BMS fault code list). Confirm the code on your own unit's display or manual before ordering parts.
More Felicity error codes
- Felicity 04Low cell voltage / over-discharge protection.
- Felicity 05PV over-current fault: the PV input current exceeded the inverter's PV input limit.
- Felicity 18PV short-circuit fault on the PV input; in the warning list the same number means battery under-voltage alarm.
- Felicity 19Battery open-circuit alarm: the inverter no longer detects a battery on its terminals.
- Felicity 20Battery SOC low alarm: the battery's state of charge has fallen to the low-SOC warning threshold.
- Felicity 21BMS communication alarm: abnormal communication between battery and inverter in non-SOC mode.
Guidance reviewed 17 October 2026 by the Mishka Energy installer team. Error codes vary by brand, model family and firmware; confirm against the manufacturer manual.
Back to troubleshooting