A generic display assembly includes a very few
parts and knowing them will help you to understand witch part can cause a
problem if you laptop video not working properly.
Video cable. A video
signal from the motherboard goes to the LCD screen through the video cable. The
video cable connects to the motherboard (or video card) through the connector
1. The video cable connects to the LCD screen through the connector 2. The
video cable (in most cases) is also responsible for supplying a necessary
voltage for the FL inverter board. The video cable connects to the FL inverter
board at the point 3.
FL inverter board. This
board is responsible for converting low voltage DC power (point 3) to high
voltage AC (point 4), necessary to light up the backlight bulb. If the FL
inverter board is bad, the LCD screen (backlight bulb) will not light up when
you turn on the laptop, but you still should be able to see a very dim image on
the screen.
CCFL (backlight bulb). When the
backlight bulb lights up, you can see an images on the LCD screen. In most
cases the backlight bulb is a part of the LCD screen and if it’s bad, the
entire screen has to be replaced. By the way, some specialized repair shops can
replace the backlight bulb itself.
Lid close switch. The lid
close switch is a small button that locates close to the display hinges. On
some newer models there is no button, because the switch is magnetic. You can
set up your laptop to go to a hibernation mode or to a standby mode when the
LCD is closed. It’s done through power management software. These modes are
triggered when the display is closed and the lid close switch is pressed down.