Cell or pack temperature exceeds safe operating limit. Charging/discharging halted until temperature drops.
Common causes
Ambient temperature above 45°CBattery in direct sunlightInsufficient ventilation clearances (min 300mm above and sides)High charge/discharge rates in warm conditions
What to check
STEP 1
Check ambient temperature at battery location. ECS operating range: 0–55°C discharge, 0–45°C charge. Ensure ventilation clearances are met
STEP 2
Allow battery to cool (typically 30–60 min). Fault self-clears when temperature returns to normal range. Provide shading or improve ventilation
Escalate if
Fault occurs repeatedly in normal ambient temperatures with adequate ventilation — NTC sensor or internal thermal fault, escalate
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