Turn on the power switch, the display does not respond, the indicator does not light.
Turn on the power switch, the indicator light is on the display without any display.
Turn on the power switch. The display is bright, with characters, fans, and no echo.
Turn on the power switch. The indicator light is on, the display is on, and there are no characters or sectors.
The panel does not work when it works normally after power-up (only the reset button works).
When the camera works normally after power on, the image signal is weak.