The Xiaomi Home Assistant has been a revolutionary tool in managing and controlling various smart devices within the home. However, a recent issue has been reported regarding the lumi.acpartner.v3 device, which is unable to control the relay switch. This article aims to delve into the problem, explore possible solutions, and discuss the expected behavior of the device. The lumi.acpartner.v3 is an upgraded version of the air conditioner companion and is designed to support control over relay switches, making it an ideal device for controlling heavy loads such as water heaters or ovens. Despite its capabilities, the device currently lacks the functionality to control the relay switch through the Xiaomi Home app, limiting its potential. To address this issue, it is essential to understand the expected behavior of the device and the steps required to reproduce the problem. The expected behavior of the lumi.acpartner.v3 is to have a control switch that allows users to turn the relay on and off, thereby controlling the flow of electricity to connected devices. However, as reported, the device does not have this functionality in the Xiaomi Home app, restricting its use. The steps to reproduce the problem involve checking the device's settings and configuration within the Xiaomi Home app, ensuring that the device is properly connected and integrated with the app. If the issue persists, it may be necessary to consult the system logs for any error messages or clues that could help resolve the problem. The system logs can provide valuable insights into the device's behavior and any potential issues that may be causing the problem. In this case, the logs did not provide any response, indicating that further investigation is required. The Xiaomi Home Integration Version, v0.2.0, and the Home Assistant Core Version, 2025.2.5, may also play a role in resolving the issue, as updates to these versions may include fixes or improvements to the device's functionality. In conclusion, the lumi.acpartner.v3 device has the potential to be a valuable addition to any smart home system, but its current limitation in controlling the relay switch must be addressed. By understanding the expected behavior of the device, reproducing the problem, and consulting system logs, users and developers can work together to resolve the issue and unlock the full potential of the device. As the Xiaomi Home Assistant continues to evolve and improve, it is essential to prioritize the development of robust and reliable smart devices that can seamlessly integrate with the platform, providing users with a comprehensive and convenient smart home experience.