It may be the change of mirror mode. At this time, you need to turn on the phone and observe the mirror mode. Choose to turn on microphone acquisition in setting image settings, and then you can set the correct image mode. If not, you need to replace the graphics card hardware or graphics card driver. In the process of replacement, you only need to click the properties of the TV, and then the corresponding dialog box pops up to compare the drivers. Choosing the right driver is helpful to the normal operation of TV. If it still doesn't work, you need to speed up the hardware to 5. It is very likely that the hardware acceleration is too large, which causes the TV to be unable to withstand its pressure and the screen is completely black. In addition, if the TV has a black screen, it is also possible that the graphics card is abnormal or even the circuit board is short-circuited. At this time, it is necessary to carry out relevant tests, and then observe whether the TV can work normally by measuring resistance and current.