Robot vacuum does not detect stairs and has nearly fallen or actually fallen off an edge.

Safety first: Immediately stop using the robot near stairs until the issue is resolved. Use physical barriers to block edges.

• Step 1 – Clean cliff sensors: Turn the robot over and clean all downward-facing cliff sensor windows with a soft cloth.
• Step 2 – Test in safe area: Place the robot near a low step or dark mat in a controlled environment and observe its behavior.
• Step 3 – Avoid problematic surfaces: Very dark or glossy floors can reduce sensor performance. Use boundary strips or barriers near stairs.
• Step 4 – Replace sensor module: If the robot still fails to detect edges, replace the Medion cliff sensor module.