My Dyson stick vacuum cleaner appears to be shutting off much earlier than its typical 20-minute runtime. How can I test it to determine if the problem lies with the battery?

To diagnose if your Dyson stick vacuum's battery is causing it to shut off too soon, follow these steps:

• Fully charge the vacuum for 3 to 4 hours or overnight.
• Set the vacuum to MAX mode and start a timer at 0:00 using your phone's stopwatch.
• While the vacuum is running, press the MAX button until it flashes blue.
• Start the stopwatch and run the vacuum until it stops.
• Note the total run time.
Interpret your results as follows:

• If the vacuum runs for about 6 minutes in MAX mode with a full battery, the battery is likely fine, and you may have a different issue.
• If it runs for 3 minutes, you may need a new battery soon.
• If it runs for less than 3 minutes, your battery needs replacement. Remember to recharge it partially and turn off MAX mode before installing a new one.