Cordless vacuum will not turn on; display briefly flashes E1 then shuts off

Safety first: Turn the power switch OFF and remove the battery pack from the vacuum before inspecting anything. Do not short the battery terminals.

• Check battery seating: Remove the battery, inspect the contacts on both the battery and vacuum for dust, hair, or oxidation. Clean gently with a dry cloth or a cotton swab lightly dampened with isopropyl alcohol. Let dry fully and reinstall the battery firmly until it clicks.
• Inspect terminals: Look for bent, recessed, or burned terminals in the battery bay of the vacuum. If any terminal is pushed in or discolored, the main control board or battery connector harness may be damaged and should be replaced.
• Try a second battery (if available): If another compatible Bissell battery (e.g., for ICONpet, Adapt Ion, or CrossWave Cordless series) works normally, the original battery pack is likely faulty and should be replaced.
• Check for wobble: Gently wiggle the installed battery. If the vacuum powers off or the code reappears when moved, the battery latch or housing may be cracked and require replacement.
• Do not open the battery pack: Bissell lithium-ion packs are not user-serviceable. If cleaning contacts and reseating does not resolve E1, replace the battery pack or contact a service center.