1. Connect to the box's WiFi (Autokit_***), password: 12345678.
2. Access backend settings via browser (192.168.50.2).
3. Turn on sync mode, and adjust the frame rate (try 20), or resolution.
Consider downgrading firmware if the black screen occurred after an update.
As a last resort, restore factory settings in the backend settings.
By following these concise troubleshooting steps, you can resolve the black screen issue with your Carlinkit 5.0 (2air) and enjoy uninterrupted connectivity.