Cordless vacuum will not power on, battery icon flashes briefly then turns off

Safety first: Turn the power switch OFF and remove the battery pack from the vacuum before any inspection. Never short battery terminals or open the battery pack housing.

• Step 1 – Check charger and outlet: Plug the Bomann charger into a known-good wall outlet. Confirm the charger LED turns on. If the charger LED stays off, test another outlet or power strip.
• Step 2 – Fully charge the battery: Insert the battery pack into the Bomann charger until it clicks. Allow it to charge for at least 3–4 hours or until the charger LED indicates full charge (refer to your model’s manual for LED behavior). Try powering the vacuum again.
• Step 3 – Clean battery contacts: With the battery removed, inspect the metal contacts on both the battery pack and the vacuum handle. If you see dullness or light corrosion, gently clean with a dry microfiber cloth. For stubborn oxidation, lightly rub with a pencil eraser, then wipe away debris. Do not use liquids or sprays.
• Step 4 – Cool down the pack: If the vacuum was used heavily and then immediately put on charge, the BMS may keep it off until it cools. Let the battery sit at room temperature for 30–60 minutes, then try again.
• Step 5 – Test with another battery (if available): If you have a second Bomann battery compatible with your model, install it and see if the vacuum powers on. If it works with the second battery, the original pack is likely defective.
• Step 6 – Replace battery pack: If E1 persists after full charging and contact cleaning, the internal BMS or cells are likely faulty. Purchase a genuine Bomann replacement battery pack specified for your cordless vacuum model and install according to the user manual.

If the vacuum still will not power on with a known-good battery, the main control PCB may be defective and should be serviced by a qualified technician.