iRobot · Robot Vacuum Moderate
Charging Error 3 — Battery won't charge
Battery is detected but won't accept a charge — usually a depleted battery, bad contacts, or dock issue.
- Keep using it?
- Yes, with caution
- DIY difficulty
- Easy
- Verified against
- homesupport.irobot.com ↗
How to fix it
- Clean the metal contacts on both the robot and Home Base with a dry cloth or pencil eraser.
- Verify the Home Base LED is solid green/on — if not, test the outlet with another device.
- Try a known-good power adapter rated for the dock if available.
- Leave robot on dock for 6+ hours to attempt to wake an over-discharged battery.
- Replace battery with iRobot OEM Li-Ion battery if it won't charge after multiple attempts.
Why it happens
Typical signs: 'Charging error 3' voice prompt · Robot docks but battery level stays the same · Charge LED behavior abnormal
- Dirty dock or robot charge contacts Poor electrical connection between dock and robot.
- Battery over-discharged Battery sat empty for weeks/months and protection circuit engaged.
- Faulty Home Base power supply Dock adapter not delivering rated voltage.
- End-of-life battery Cells will no longer hold charge.
Parts you may need
If diagnosis points to a failed part, these are the common replacements. As an Amazon Associate we earn from qualifying purchases.
More iRobot robot vacuum codes
Charging Error 2 Charging Error 2 — Battery not detected Charging Error 5 Charging Error 5 — Charging system fault Error 1 Error 1 — Side wheel stuck / off ground Error 10 Error 10 — Drive wheel not turning Error 11 Error 11 — Bin full or airflow blocked Error 14 Error 14 — Bin not detected / not installed correctly
Always unplug an appliance before servicing it. This guide is for informational purposes and is not a substitute for a qualified technician. Verified against manufacturer documentation: homesupport.irobot.com.