Robot vacuum displays E5 and will not start or complete a cleaning cycle.

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

• Remove the side brush: Use a screwdriver (if required) to remove the screw holding the side brush, then pull the brush off the motor shaft.
• Clean the brush: Remove hair and fibers from the bristles and hub. Ensure the hub hole is not rounded out or cracked.
• Inspect motor shaft: Check for hair wrapped around the shaft and remove it with tweezers. Spin the shaft gently by hand; it should turn smoothly.
• Reinstall or replace brush: If the brush is damaged, install a new side brush. Reattach securely.
• Test operation: Power on the robot and start a cleaning cycle. Observe whether the side brush spins normally.
• If E5 remains: The side brush motor or gearbox is likely failing. Replace the side brush motor module.