Charger LED flashes red or shows error when battery is inserted (no specific code on vacuum)

Safety first: Unplug the charger before inspecting connectors. Do not charge a visibly damaged battery.

Step-by-step checks:

• 1. Allow battery to cool: If the battery is warm from use, let it cool to room temperature before charging again.
• 2. Clean contacts: Wipe the charger and battery contacts with a dry cloth. Ensure there is no debris in the charger slot.
• 3. Try another outlet: Plug the charger into a different wall outlet to rule out power issues.
• 4. Test with another battery (if available): If a second battery charges normally, the original pack is faulty. If both fail, the charger may be defective.

When to stop: Replace the charger or battery as indicated by testing; do not attempt to open the charger.