Vacuum displays E5 and will not run; may occur after battery replacement or long storage.

Safety first: Do not attempt to open the battery pack. Lithium-ion batteries can be hazardous if punctured or shorted.

• Check battery seating: Remove the battery pack and reinstall it firmly until it clicks. Ensure there is no play or looseness.
• Inspect contacts: Examine the metal contacts on both the battery and the vacuum body. If dirty or oxidized, gently clean with a dry cloth. Do not use liquids.
• Fully charge the battery: Place the battery on the original Tineco charger or dock. Allow it to charge until the indicator shows full. This may take several hours if the battery was deeply discharged.
• Try a different outlet/charger: If available, test with another compatible Tineco charger to rule out a charger fault.
• Test with another battery (if available): If a second compatible battery works normally, the original battery pack is likely defective and should be replaced.
• Do not bypass safety: If E5 persists, do not attempt to jump-start or modify the battery. Replace the battery pack with an original Tineco part.