Carpet cleaner leaves black or dark marks on the carpet

Safety first: Unplug before inspecting the underside of the machine.

• Inspect brush bar and base plate: Look for grease, oil, or dark buildup. Clean with a mild detergent and damp cloth, then dry thoroughly.
• Check wheels: Spin wheels and inspect for worn rubber or embedded debris. Replace if they are deteriorating.
• Look for exposed metal: Ensure no screws or metal edges are protruding from the base plate.
• Test on scrap area: After cleaning, test on an inconspicuous area of carpet to confirm marks no longer appear.