Robot mower is very loud during operation, with grinding or rattling noises from underneath.

Safety first: Turn off the main switch and wear hearing and cut protection when inspecting moving parts.

• Identify noise source: Run the mower briefly while lifted slightly (by a technician) or listen carefully as it operates to determine if the noise comes from the cutting deck or wheels.
• Inspect blades and disc: With power off, check that the blade disc is firmly attached and that all blades are present and secure. Replace damaged blades and tighten disc mounting bolts to AL-KO torque specs.
• Check for debris: Remove grass and twigs from around the blade motor and wheel motors. Foreign objects can rub against rotating parts.
• Spin components by hand: Rotate the blade disc and wheels manually. Roughness or grinding indicates bearing or gearbox wear.
• Replace worn parts: If noise persists, replace the blade motor assembly or affected wheel motor/gearbox.