Cordless vacuum stops shortly after starting, LED flashes red in a repeating single-blink pattern

Safety first: Turn the vacuum OFF and remove the battery pack before any inspection. Do not open the battery pack housing.

• Fully recharge the battery: Place the Black+Decker 18V/20V MAX lithium-ion battery pack on its original charger. Allow it to charge until the charger indicator shows a full charge (steady green or as specified in the manual).
• Check charger and contacts: Inspect the battery terminals and the vacuum's battery contacts for dust, corrosion, or debris. Clean gently with a dry cloth. Do not use liquids or metal tools.
• Test run time: After a full charge, reinstall the battery and run the vacuum on low and then high speed. If it shuts off within a minute and the E1 pattern repeats, the pack may be failing.
• Try a second battery: If available, test with another compatible Black+Decker lithium-ion battery. If the issue disappears, the original battery pack is defective.
• Replace the battery pack: If the battery repeatedly triggers undervoltage protection despite full charging, replace it with a genuine Black+Decker lithium-ion battery of the correct voltage and capacity.

Do not attempt to open or repair the battery pack; swollen, hot, or leaking packs must be recycled immediately according to local regulations.