My robotic vacuum cleaner shows error E21, warning triangle and Play button are blinking

Issue

• My robot shows error message E21
• Warning triangle and Play button are blinking after the robot has been in the charger

Applies to

• robotic vacuum cleaner

Resolution

1. Update the robot software via the app or via the website dedicated download link

2. If the problem persists after the update:

• Check if both batteries are properly connected and reset the robot by unplugging the batteries and wait 10 seconds. Reinstall the connectors and check if the problem is resolved.
• If not, then you may need to replace both battery packs to remove this error code.
• Put it back in the charging stand and restart it after charging is complete.
  AEG offers 6 months warranty on batteries.

Cause

• The error code means that the battery charge is not completed normally or that charging has taken too long.
• The reason may be that the batteries are worn or otherwise defective.