The LCD screen flicker is usually caused by poor contact, such as the poor contact of the power supply three-hole socket due to multiple plugging and heating.
The biggest possibility is that on the high-voltage driving board of the display, the switch transistor and the resonant small capacitor responsible for triggering the lighting of the lamp tube are caused by the long-time operation of the lamp tube and the aging of the lamp tube, and the pin and the capacitor foot have a small length of time. Disengaged from solder, causing poor contact failure. Please open the machine and re-weld it all over the body.
If the lamp of the LCD panel is aging black, it is necessary to change it.