The vacuum stops suddenly during use; the motor cuts out and an overheat or E03 indicator flashes.

Safety first: Switch off the vacuum and remove the battery pack before clearing blockages or opening any covers.

• 1. Allow cooling: Let the vacuum sit powered off for at least 30 minutes so the thermal protector on the motor can reset.
• 2. Check for blockages: Detach the floor nozzle, wand, and handheld unit. Look through each section for clogs (dust plugs, toys, paper). Remove obstructions with a non-sharp tool.
• 3. Clean dust container: Empty the Grundig dust bin completely. Tap out compacted dust from the cyclonic cone and mesh screen.
• 4. Wash filters: Remove the pre-motor filter and HEPA exhaust filter (if washable on your model). Rinse under lukewarm water until clear. Squeeze out excess water and let them air-dry for at least 24 hours before reinstalling. Never run the vacuum with wet filters.
• 5. Inspect brush roll: Open the floor head and remove the brush roll. Cut away hair, threads, and fibers from the roller and end caps. Ensure the roller spins freely in its bearings.
• 6. Test again: Reassemble and run the vacuum. If E03 or an overheat warning returns quickly with clean filters and no blockages, the main suction motor may be failing and should be replaced by a technician.