Robot vacuum reports C1 and will not start cleaning; may say 'Please check the left wheel' or spin in circles.

Safety first: Turn the robot OFF and remove it from the charging dock. If possible, remove the battery or ensure the power switch is in the OFF position.

Step-by-step:

• Inspect the left wheel: Flip the Ecovacs robot over on a soft surface. Manually rotate the left drive wheel. It should turn freely and spring up and down.
• Remove debris: Use tweezers or scissors to cut and pull out hair, threads, and dust wrapped around the wheel hub and axle. Check the wheel well for trapped objects (toys, stones, glass).
• Clean the encoder area: On many Ecovacs models, the wheel has an internal encoder. Blow compressed air into the wheel cavity and gently tap the wheel to dislodge fine dust that may block the sensor.
• Check suspension movement: Press the wheel up and down. If it is stuck, gently work it up and down while cleaning around the pivot points with a soft brush.
• Power cycle: Turn the robot back on, place it on a flat floor, and start a cleaning cycle to test.

If the error persists: The left wheel motor or encoder assembly is likely failing and the entire left wheel module should be replaced. This usually requires opening the bottom cover; if you are not comfortable with disassembly, contact an authorized Ecovacs service center.