A Chromecast that won't show up in the Google Home app during setup is rarely a dead dongle. The phone finds the Chromecast first over Bluetooth, then moves it onto your Wi-Fi — and "can't find device" means one of those two handoffs broke. Almost every case is a network band, a Bluetooth/permissions setting, or a power issue on the phone side, not the Chromecast.
Fix it
- Get your phone on the right Wi-Fi band. Chromecast setup is happiest on 2.4 GHz. If your router broadcasts one combined network and your phone is on the 5 GHz side, the app can't complete the handoff. Temporarily split the bands (or join the 2.4 GHz SSID) and retry.
- Turn on Bluetooth and Location — and grant the app permission. The Home app discovers a new Chromecast over Bluetooth, and on Android it needs Location permission to do Wi-Fi/Bluetooth scanning. In the phone's app settings, allow Bluetooth and Location for Google Home, then reopen it.
- Power the Chromecast from the wall, not the TV's USB port. A TV USB port often can't supply enough power, and an underfed Chromecast drops off Wi-Fi or won't broadcast for setup. Use the included power adapter in a wall outlet.
- Reboot the phone and the router. A stale Bluetooth or network stack on the phone is a common cause — restart it, power-cycle the router (off 30+ seconds), and start setup fresh.
- Disable VPN and client isolation. A VPN on the phone, or "AP/client isolation" on the router, stops the phone and Chromecast from seeing each other. Turn both off for setup.
If it still won't appear
Factory-reset the Chromecast and start over: on the dongle, press and hold the button on the side (the light turns solid, then starts blinking — keep holding until it reboots). Then run setup again with the steps above in place. A reset clears a half-finished previous setup that can block a new one.
Why the band matters so much
This is the part people miss: even if your Chromecast and phone are both "on Wi-Fi," setup fails if they're on different bands or different SSIDs (including a guest network). The Home app has to talk to both on the same segment to move the Chromecast onto your network. Matching them on one 2.4 GHz network resolves the large majority of "can't find device" failures.
FAQ
Why can't the Google Home app find my Chromecast? Usually your phone is on 5 GHz (or a guest network) while setup needs 2.4 GHz, or Bluetooth/Location permission is off. Match the band and grant the permissions.
Does it really need Bluetooth? Yes — the app discovers a new Chromecast over Bluetooth before moving it to Wi-Fi. Turn Bluetooth on and allow it for the Home app.
Mine's plugged into the TV's USB port — is that a problem? Often, yes. TV USB ports can underpower a Chromecast, causing it to drop off during setup. Use the wall adapter.
It still won't show up after all that. Factory-reset the Chromecast (hold the side button until it reboots) and run setup again with Bluetooth, Location, and the 2.4 GHz band sorted first.
Once setup completes, if the Chromecast starts turning your TV on or grabbing the input on its own, that is a separate control-channel issue covered in our guide to Chromecast with Google TV HDMI-CEC problems.