TOPトラブルシューティング(英語)Troubleshooting(Y!mobile 305ZT/304ZT)
最終更新日 : 2026/06/24

Troubleshooting(Y!mobile 305ZT/304ZT)

This guide applies only to devices with a management number starting with "LG..." (found on the label on the back of the device).

f your device is not working properly, please try the following steps.

Note: Performing a reset will clear the data usage displayed on the screen back to "0."

<Restarting the Device>

Turn the power off, then turn it back on.

<Reinserting the Battery>

With the power turned off, remove the back cover and the battery, then reinsert them.

<Reinserting the SIM Card>

(1) Insert SIM tool: With the power turned off, insert the SIM tool into the small hole at the bottom of the device.
(2) Remove SIM tray: The SIM tray will eject, so please pull it out.
(3) Reinsert: Place the card facing the correct direction and reinsert the tray.

Note: If you do not have a SIM tool, you can use a thin, pointed object such as a needle.

LGリセット.png

<Resetting the Device>

(1) Power On: Turn the power on.
(2) Open Settings: Tap "Settings" (設定) on the menu screen.
(3) Select Reset: Tap "Reset" (リセット) at the bottom of the screen.
(4) Confirm Initialization: A message will appear asking, "Initialize to factory defaults. Are you sure?" (工場出荷の状態に初期化します。よろしいですか?). Select "Yes" (はい).
(5) Restart: The device will reset and restart automatically.
(6) Complete Setup: After the device restarts, press "OK" twice to complete the process.