Symptoms
- Bulb shows offline or unreachable in the app
- Voice commands and app taps do nothing
- Bulb turns on with the wall switch but won't respond to smart controls
- Bulb worked before and stopped suddenly
Likely causes
- CommonWall switch turned off, cutting power to the bulbA smart bulb loses its Wi-Fi/hub connection entirely if the physical switch controlling it is off, since it has no power.
- CommonLost Wi-Fi or hub connectionA router restart, password change, or weak signal can disconnect the bulb from the network.
- PossibleBulb needs a power cycle to reset its connectionSmart bulbs occasionally need a brief power interruption to reconnect properly.
- PossibleToo many devices on the smart home hub or networkSome hubs or routers have a device limit that can cause the newest or farthest device to drop.
- Less commonBulb hardware failureSmart bulbs have more electronics than standard bulbs and can fail outright over time.
What to do
- Check that the wall switch controlling the bulb's socket is left in the 'on' position at all times.
- Turn the power to the bulb off for 10 seconds and back on to force a reconnect attempt.
- Check your Wi-Fi or hub status to make sure it's online and the bulb's network hasn't changed.
- Move any hub or extender closer to the bulb's fixture if signal seems weak.
- Remove and re-add the bulb in the app if it still won't reconnect.
- Test the bulb in a different fixture to rule out a wiring or socket issue at its current location.
- Replace the bulb if it fails to respond even when freshly connected in a known-good socket.
Tools and parts
Replacement smart bulbSearch: “smart wifi light bulb”
When to call a pro
No professional needed; if bulbs fail often, an electrician can check for voltage fluctuations at that circuit.
Safety
Generally low risk
Generally low risk for a careful person. Stop if anything looks different from what this guide describes.