Robot reports E5 and stops; often occurs when approaching stairs or dark carpets.

Safety first: Turn off the robot and keep it away from stairs while testing.

Clean the cliff sensors:

• Locate the cliff sensors on the underside front edge of the Tesvor robot (usually 3–6 small infrared windows).
• Use a soft, dry microfiber cloth to gently wipe each sensor window. If there is sticky dirt, lightly dampen the cloth with water (no solvents) and wipe, then dry immediately.
• Ensure there is no tape, stickers, or protective film covering the sensors.

Test on a safe surface:

• Place the robot on a light-colored, flat floor away from edges.
• Power it on and start cleaning. Observe whether it still reports E5.

If the error persists: The cliff sensor module or its wiring may be faulty. Do not bypass or cover cliff sensors, as this can cause falls and damage. Contact Tesvor support or a technician to test and replace the cliff sensor board or harness.