Nest Doorbell (wired, 2nd gen) firmware update is stuck or failed

The checks in more detail

A weak Wi-Fi signal can stall the download, so check the signal at the door. A doorbell on a weak transformer can fail an update because the restart needs power, so check the wiring if updates repeat. Do not press the button during an update, and do not cut the doorbell's power at the breaker while the light shows an update. If the version has not changed for weeks, the doorbell may not be online or Google may not yet have released a new version to your device, as updates roll out in stages.

Make sure the doorbell is online and that it is not in a long offline loop. Restarting the router and the doorbell can help it check for updates. After an update, the doorbell may need a minute to come back, and settings stay as they were. If the update fails and the doorbell shows a persistent error light, restart it, and, if it persists, contact Google Nest support. Keep the Google Home app updated, since an old app may not show the newest features. If you moved house and reset the doorbell, it updates after setup.

A factory reset does not downgrade the firmware, so do not expect it to remove a faulty update. If you need to confirm that the update has happened, compare the version number before and after across two days, and note any date in the app's device information. An update that seems to repeat may mean the doorbell is restarting during installation because of low power, which the power page covers. Keep the Google Home app signed in, since the doorbell checks in with your account when it updates. If you share the doorbell, only the owner's account shows the firmware details.