Display or LED shows 'LO' or continuous slow red flashing, vacuum runs only briefly or not at all

Safety first: Use only the original or approved charger for your Black+Decker cordless vacuum.

• Fully charge battery: Place the battery or the whole vacuum (for built-in packs) on the charger until the indicator shows full. This may take several hours.
• Verify charger operation: Ensure the charger LED behaves normally (not flashing error). Plug the charger into a known-good outlet.
• Clean contacts: Remove the battery and wipe the contacts on both the battery and charger with a dry cloth.
• Test runtime: After a full charge, run the vacuum continuously on low. If it stops within a few minutes and shows LO again, the battery capacity is likely degraded.
• Replace battery or charger: Replace the battery pack if runtime is short. If a second battery behaves the same, the charger may be faulty and should be replaced.