Cordless vacuum will not power on, battery LEDs flash once then go dark

Safety first: Disconnect the battery pack from the vacuum before any inspection. Never open or puncture a lithium battery pack. If the pack is swollen, hot, or leaking, stop and dispose of it at a battery recycling center.

Steps to try:

• 1. Check charger and outlet: Plug the Hoover Candy OEM charger into a known-good wall outlet. Confirm the charger's indicator light comes on. If the charger LED is off or flickering, test with another outlet or a different compatible charger.
• 2. Inspect battery contacts: Remove the battery pack from the vacuum. Inspect the metal contacts on both the battery and the vacuum handle for corrosion, burning, or bent pins. Clean light oxidation with a dry cloth; do not use liquids. Ensure the pack clicks firmly into place when reinstalled.
• 3. Attempt a recovery charge: Place the battery on the charger for at least 3–4 hours, even if the LEDs do not immediately light. Some Hoover Candy packs need a few minutes before the BMS wakes up and shows charging status.
• 4. Test on-tool behavior: After charging, refit the battery and press the power trigger. If the E1 indication (single flash then off) persists and the vacuum never starts, the BMS has likely locked out the pack due to cell damage or undervoltage.
• 5. Replace battery pack: If a known-good charger and outlet have been verified and the vacuum still shows E1 behavior, replace the complete Hoover Candy lithium battery pack with the exact model specified in your user manual. Do not attempt to rebuild or open the pack.

When to call a technician: If a new OEM battery does not resolve the issue, the fault may be in the vacuum's internal power board or battery connector harness, which should be tested and replaced by a qualified service center.