An E01 error on the Smart AC Control indicates a timeout issue with the Wi-Fi connection. In most cases, the connection fails due to an incorrect Wi-Fi password.
To fix this, please do the following:
Wait until the display of your Smart AC Control shows the 4-digit code again. This means that the device is ready to connect to Wi-Fi.
If the issue persists, make sure your Wi-Fi is activated and working. To do so, check Wi-Fi access on other devices or the LEDs on the front of your router.
Please note: when the internet connection is temporarily lost, you can control your AC via the user interface on the Smart AC Control. You can also use your old AC remote for this.