Vacuum shows E9 or a battery icon with an exclamation mark, cannot charge fully or stops charging early

Safety first: Unplug the charger from the wall before handling the charging dock or power adapter.

• Normalize temperature: If the vacuum or battery feels hot, let it cool at room temperature for at least 1 hour before charging. Avoid charging in very cold environments (below 5°C) or hot areas (above 35°C).
• Check charging contacts: Inspect the dock or charging port and battery contacts for dust or oxidation. Clean gently with a dry cloth.
• Try direct charging: If your model supports both dock and direct plug-in charging, try the alternative method to rule out a faulty dock.
• Test another outlet/charger: Use a different wall outlet. If available, test with a known-good original Xiaomi charger of the same rating.
• If error repeats at normal temperature: The battery's internal temperature sensor or BMS is likely faulty. Replace the battery pack. If a new pack shows the same error, the charging PCB or dock should be replaced.