failure mode
Roomba i3+ Charging Error 1 — Battery not detected
Symptom: On the dock or charger the robot reports the battery isn't detected / connected and won't charge. Likely root causes: Battery not seated / loose after a replacement; Yellow plastic pull-tab still in place on a new unit; Battery contacts dirty or corroded; Battery completely flat (deep discharge) Next steps if owner-level checks fail: Battery still not detected after reseating with clean contacts — the pack is likely dead; fit a genuine iRobot replacement; A brand-new genuine battery still not detected — robot charge circuit may be faulty; contact iRobot Customer Care 1-877-855-8593