![image01](https://umanual-e.hometact.biz/hs-fs/hubfs/hometact/images/manual-e/case/replace-battery-in-opelo/image01.png?width=266&height=354&name=image01.png)
If you receive the following response from the device when unlocking, it is time to replace the batteries. Please replace the batteries as soon as possible.
- The "Open/Close button" lights up red (normally blue).
- One phrase of the "Twinkle, twinkle, little star" melody is played.
● Knowledge
- Use four AA alkaline or AA lithium batteries.
- Do not misorient the batteries. Doing so may cause malfunctions.
- Do not mix old and new batteries.
- Be sure to use alkaline batteries made by a Japanese manufacturer.
- Inserting batteries other than alkaline batteries may cause malfunction.
- If the battery has run out and the lock cannot be unlocked, please refer to "When OPELO cannot be unlocked due to a dead battery" for how to unlock the lock.
- After replacing the batteries, check the operation of unlocking the lock from an IC card or a smartphone equipped with NFC function.
1.
![image02](https://umanual-e.hometact.biz/hs-fs/hubfs/hometact/images/manual-e/case/replace-battery-in-opelo/image02.png?width=319&height=409&name=image02.png)
Remove the battery cover on the interior side.
2.
![image03](https://umanual-e.hometact.biz/hs-fs/hubfs/hometact/images/manual-e/case/replace-battery-in-opelo/image03.png?width=319&height=409&name=image03.png)
Remove the old battery.
3.
![image04](https://umanual-e.hometact.biz/hs-fs/hubfs/hometact/images/manual-e/case/replace-battery-in-opelo/image04.png?width=319&height=410&name=image04.png)
Press the Open/Close button three times.
4.
![image05](https://umanual-e.hometact.biz/hs-fs/hubfs/hometact/images/manual-e/case/replace-battery-in-opelo/image05.png?width=319&height=410&name=image05.png)
Replace with new batteries.
5.
![image06](https://umanual-e.hometact.biz/hs-fs/hubfs/hometact/images/manual-e/case/replace-battery-in-opelo/image06.png?width=319&height=407&name=image06.png)
Install the battery cover.