Robot reports E11; battery level may drop quickly or robot shuts off unexpectedly.

Safety first: Turn off the robot and remove it from the dock.

• Access battery: Remove the battery cover on the underside (usually held by a few screws).
• Check connections: Ensure the battery connector is firmly plugged into the robot's harness and shows no signs of burning or corrosion.
• Inspect battery: Look for swelling, leakage, or damage. Do not use a damaged battery.
• Replace battery: If the robot is older or runtime has significantly decreased, install a new, compatible Eureka Robot Vacuum Battery Pack.
• If E11 continues with a new battery: The battery sensing circuit or temperature sensor on the main PCB may be faulty. Main board replacement is recommended via a service center.