LED indicator shows a battery with an exclamation mark; vacuum stops under load even with a charged battery.

Safety first: Remove the battery before cleaning contacts.

• Use a higher-capacity pack: Try a newer, higher Ah Ryobi ONE+ battery (e.g., 4.0Ah or 5.0Ah) to reduce voltage sag under load.
• Clean contacts: Wipe battery and tool terminals with a dry cloth. Lightly polish with a pencil eraser if oxidized, then wipe clean.
• Check battery on other tools: Use the same battery in another Ryobi ONE+ tool under load. If it also cuts out, replace the battery.
• Inspect terminal tension: Ensure the battery locks firmly into the vacuum. If it feels loose, the terminal springs inside the vacuum may be worn.

If good batteries still trigger under-voltage warnings only on this vacuum, the internal sensing circuit or control board may be defective and should be replaced.