BMS has detected an issue with one or more battery modules.
Common causes
Battery module DC connector not fully seated (BAT+ / BAT−)RJ45 BMS communications cable loose or unplugged between modulesBattery module temperature out of range (below -25°C or above 60°C operating limit)Battery module dropped or physically damagedModule count in app config does not match physical modules installedTwo-column installation: inter-column DC connector not fitted
What to check
STEP 1
Check all DC connectors (BAT+ / BAT−) are fully seated and clicked
STEP 2
Check all RJ45 BMS cables between modules are clicked in at both ends
Escalate if
All connections verified, damage or swelling visible — do NOT reconnect. Call Anker UK +44 (0) 1616 056 301
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