1, the cable between the TV and the set-top box is not in good contact or the cable is faulty, resulting in no signal on the TV after connection. You can change the connection line and reconnect it.

2. If the signal source of the TV is not switched to the corresponding mode, resulting in no signal display, you can press the signal source key of the TV remote controller to pop up the signal source menu option, and then switch the signal source modes one by one until the picture of the set-top box is displayed.

3. Hardware failure of the TV or set-top box leads to no signal on the TV display, such as interface failure, connection circuit failure between the interface and the motherboard, signal processing device failure, and other parts of the motherboard chip failure. Need to contact TV after-sales service to conduct a comprehensive overhaul of the TV.