1. It may be that the hdmi cable is damaged, or it does not match the interface of the connected device, which will cause the switch to connect the TV with a black screen. 2. Initialize the hdmi cable settings. Unplug the TV completely and turn it on again. The hdmi module will be reinitialized only when it is completely turned off and turned on again.
Suggested treatment:
1. First of all, you have to have a TV, preferably LCD, which can connect to the Internet. Connect the AC transformer to the top jack and the HDMI to the bottom jack. You need to connect the other end of HDMI to the TV, usually on the back of the TV. Joy-Con needs to be removed from the switch host. Plug the host into the switch. When the power supply is plugged in, the switch will display green light, and the host diagram will be black. Turn on the TV, switch to HDMI mode with the remote control board, and you can use it.
2. Try to switch the TV signal source, because after the switch is connected to the TV, it will not jump directly to the switch display interface. You must switch to the connected signal source before TV settings can find the signal source to choose from.
3. Ensure that the switch base must use the original charger.
4. In the case of using the host mode, the original power charger must be used. If you use some mobile phone chargers, it will definitely not work, and it is very easy to cause hardware loss.
5. If there is something wrong with the switch interface, you will not be able to connect. Generally it can be repaired. You can try to borrow someone else's base first to rule out whether it is the switch itself.