Inverter has lost CAN or RS485 communication with the ECS battery BMS. Battery will not charge or discharge.
Common causes
CAN/RS485 cable not seated at battery CM bottom port or inverter BMS portWrong DIP switch setting on CM moduleFirmware version mismatch between CM hardware generations (V1 vs V2)Faulty communication cable
What to check
STEP 1
Check CAN/RS485 cable is fully seated at the CM (controller module) bottom port and the inverter BMS port. Collar screw must be tight. Use Torx T10 if required
STEP 2
Check DIP switch on CM: for V2 hardware leave at position 0 (auto). For V1 set to match number of CS modules. Check Fox Cloud app for BMS protocol setting — must match battery type
Escalate if
Cable confirmed good and DIP switch correct — swap communication cable. If still failing, escalate with hardware version details
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