FoxESS
Error 14
BMS Lost / BMS Communication Error
Inverter has lost communication with the battery BMS. Battery will not charge or discharge.
Common causes
CAN/RS485 communication cable not connected or looseWrong BMS protocol selected in appFaulty communication cableBattery powered off
What to check
STEP 1
Check BMS communication cable is firmly seated at both the battery and inverter terminals. Use the correct port (CAN or RS485 per battery type)
STEP 2
In Fox ESS app, confirm the battery type and communication protocol match the installed battery. Power cycle battery and inverter
Escalate if
Communication cable confirmed good and battery type setting correct — escalate
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