1. Press the "On/Off" button on the remote control to turn off the air conditioner.
2. Press and hold the "Mode" and "Temperature+"buttons on the remote control, and at the same time press the "On/Off" button on the air conditioning panel until the "Lock" indicator on the panel flashes.
3. Release all buttons, and then press the "On/Off" button on the remote control again to turn on the air conditioner.
4. Press the "Lock" button on the air conditioning panel until the indicator light goes out, indicating that the panel has been unlocked.
If the above steps cannot unlock the panel, it is recommended that you check the operating instructions of Hitachi Air Conditioning or contact Hitachi Customer Service for consultation.