Robot vacuum shows E2 and stops shortly after starting, often near stairs or edges.

Safety first: Turn the robot OFF and remove it from the edge of stairs or elevated surfaces.

• Locate cliff sensors: On Coredy robots, cliff (anti‑drop) sensors are small dark windows on the underside near the front edge (usually 3–4 sensors).
• Clean sensors thoroughly: Use a soft, dry cloth or cotton swab to wipe each sensor window. For stubborn grime, lightly dampen the cloth with water or isopropyl alcohol, then dry immediately. Avoid dripping liquid into the openings.
• Test on different flooring: Place the robot on a light‑colored, non‑reflective hard floor away from edges and start a cleaning cycle. Highly reflective black or glass floors can trigger false cliff readings.
• Check sensor harness: If comfortable opening the unit, remove the bottom cover (after removing the battery) and inspect the cliff sensor harness connection to the main PCB. Reseat the connector firmly.

If E2 continues on normal flooring after cleaning and reseating, the cliff sensor module may need replacement.