MOS undertemperature.
C08 on a Felicity unit indicates: MOS undertemperature.. It is a fault-severity event that can appear on 17 different devices in the Felicity catalog. The same code may have slightly different recommended fixes depending on the device — the per-device sections below show the exact wording from each device's official manual.
Fault codes stop normal operation but the unit may attempt to recover. Common causes are out-of-range conditions (voltage, current, temperature) that require checking inputs and outputs before restart.
C08 is triggered when the unit's protection or monitoring logic detects the specific condition described above. The exact trigger depends on the device — see the per-device sections for the official manual entry for each.
MOSFET under-temperature fault. LED pattern: LED1 OFF, LED2 OFF, LED3 OFF, LED4 ON.
1. The internal temperature is lower than the limit range. 2. The ambient temperature may be too low.
Check whether the ambient temperature is too low.
Felicitysolar FLA12100 12.5Kwh Battery Energy Storage System User Manual.pdf · page 1MOSFET temperature is too low.
1. The internal temperature is lower than the limit range. 2. Ambient temperature is too low.
Check whether the ambient temperature is too low.
Felicitysolar FLA48200 48V 200Ah 10kWh Lithium Phosphate Battery User Manual.pdf · page 12MOSFET (power switch) temperature is below the protection limit.
1. The internal temperature is lower than the limit range. 2. Check whether the ambient temperature is too low.
Raise ambient/inner temperature; verify ambient temperature is within the operating range.
6peluqppy_66a93554057c8.pdf · page 12MOS undertemperature.
1. The internal temperature is lower than the limit range. 2. Check whether the ambient temperature is too low.
FLA48250-EU_Manual.pdf · page 8MOSFET (BMS power switch) under-temperature protection.
1. The internal temperature is lower than the limit range. 2. Check whether the ambient temperature is too low.
Raise ambient temperature into operating range (charging 0-55°C; discharging -20-55°C); restart the unit. if the error persists, return to repair center.
felicitysolar FLA48500 LiFePO4 Battery System for Households User Guide.pdfMOS (MOSFET) undertemperature. Internal MOSFET temperature is below the lower limit.
1. The internal temperature is lower than the limit range (Innentemperatur unter dem Grenzbereich). 2. Ambient temperature may be too low.
Check whether the ambient temperature is too low. Move the battery indoors or warm the environment before restarting. Charging range: 0 deg C to +55 deg C.
Benutzerhandbuch - Felicity FLS48100SG2.pdfMOSFET (BMS power switch) under-temperature protection.
1. The internal temperature is lower than the limit range. 2. Check whether the ambient temperature is too low.
Raise ambient temperature into operating range (charging 0-55°C; discharging -20-55°C); restart the unit. if the error persists, return to repair center.
HE-GF-FLA-48500 Manual_20250327_EN.pdfMOSFET / BMS power-stage under-temperature fault displayed on the LCD BMS fault code / flag screen (section 4.4).
1. The internal temperature is lower than the limit range. 2. Check whether the ambient temperature is too low. (Per section 1.3 item 13 the unit must not be installed below 0 degC; charging range per section 2.3 is 0-55 degC.).
1. The internal temperature is lower than the limit range. 2. Check whether the ambient temperature is too low. Move the battery to a warmer environment within the operating range before resuming use.
358-010291-07.pdf · page 8MOSFET (power switch) temperature is below the operating limit.
Internal temperature is lower than the limit range; ambient temperature may be too low.
1. The internal temperature is lower than the limit range. 2. Check whether the ambient temperature is too low.
Manual-LPBF48200-H.pdf · page 101. The internal temperature is lower than the limit range. 2. Check whether the ambient temperature is too low.
Felicitysolar LPBF48350 17.5kWh 48V Solar Battery Pack with BMS User Guide.pdfThe internal temperature is lower than the limit range. Check whether the ambient temperature is too low.
Check whether the ambient temperature is too low; warm the environment. if the error persists, return to repair center.
LUX-E-48100LG03-Lithium-Battery-User-Guide.pdf · page 121. The internal temperature is lower than the limit range. 2. Check whether the ambient temperature is too low.
1. The internal temperature is lower than the limit range. 2. Check whether the ambient temperature is too low.
LUX-E-48200LG03-Lithium-Battery-User-Guide.pdf · page 121. The internal temperature is lower than the limit range. 2. Ambient temperature may be too low.
Check whether the ambient temperature is too low.
LUX-E-48230.250LG03-Lithium-Battery-User-Guide.pdfMOS undertemperature.
1. The internal temperature is lower than the limit range. 2. Check whether the ambient temperature is too low.
LUX-X-48050LG01-low-voltage-battery-user-guide.pdf · page 17MOSFET (power switch) temperature is below the lower protection limit.
1. The internal temperature is lower than the limit range. 2. Check whether the ambient temperature is too low.
Raise ambient temperature above the operating minimum; if the error persists, return to repair center.
LUX-X-48100LG01-Litium-Battery-User-Guide.pdf · page 17MOSFET (power switch) temperature is below the lower protection limit.
1. The internal temperature is lower than the limit range. 2. Check whether the ambient temperature is too low.
Raise ambient temperature above the operating minimum; if the error persists, return to repair center.
358-S010024-03LUX-X-48100LG01-User-manual_compressed.pdf · page 23The internal temperature is lower than the limit range. Check whether the ambient temperature is too low.
Check whether the ambient temperature is too low; warm the environment. if the error persists, return to repair center.
LUX-Y-4828048300LG01-Lithium-Battery-User-Guide.pdf · page 8Compiled from official Felicity user manuals. Always consult your device manual and a qualified technician before performing repairs.