Vacuum runs only at low power; turbo or max mode cannot be activated and E05 or a power-limit icon appears.

Safety first: Remove the battery pack before cleaning filters or opening any covers.

• 1. Clean dust bin and filters: Empty the dust container and clean the cyclonic mesh. Remove the pre-motor and HEPA filters. Tap them gently to remove dust, then wash if your Grundig model allows. Let them dry completely (24 hours) before reinstalling.
• 2. Check for blockages: Inspect the wand, hose (if present), and nozzle for partial clogs that could increase suction load.
• 3. Fully charge battery: Place the vacuum on charge until the battery indicator shows full. Weak batteries can cause the control board to block turbo mode.
• 4. Try turbo with bare handheld unit: Remove the wand and nozzle and run only the handheld unit. Attempt to activate turbo. If turbo works on the handheld but not with the floor head attached, the nozzle or wand may be drawing too much current.
• 5. If turbo never works: With a known-good battery and clean filters, persistent E05 suggests a fault in the main control PCB or power button/turbo switch. Replacement of the control PCB should be done by a service technician.