Cordless vacuum runs but makes a loud high‑pitched whine from the motor area

Safety first: Remove the battery before opening the housing. Do not run the motor with covers removed.

• Check for simple obstructions: Remove dust container and filters. Inspect the air inlet to the motor for foreign objects. Remove any debris carefully.
• Listen for grinding: With the unit reassembled, briefly run the vacuum. A metallic grinding or rising pitch usually indicates bearing wear.
• Avoid prolonged use: Continued use with failing bearings can cause overheating and further damage.
• Replace motor assembly: On most Kärcher cordless vacuums, the motor is a sealed module. Replacement of the entire motor assembly is recommended via an authorized service center.