Vacuum will not start unless the charger is plugged in, and stops immediately when unplugged

Safety first: Do not attempt to open the battery pack; this is hazardous.

• Check battery indicator: If the battery shows no LEDs or error when the test button is pressed, it is likely defective.
• Test with another battery: If available, install a second Medion battery. If the vacuum works normally, replace the original battery.
• Do not bypass safety: Never attempt to jump-start or bypass the battery protection circuit.
• Dispose properly: Recycle the failed battery at an authorized e-waste or battery collection point.