• LCD screens can have problems with backlighting and power sources.laptop image by Jorge Figueiredo from Fotolia.com
  
  LCD stands for liquid crystal display, a popular type of display screen that uses layers of liquid crystals that shift in response to an electrical current, allowing them to change color. These LCD layers are supported by a backlight system that shines light through the crystals to illuminate the image. LCD screens are used in many electronic devices, especially laptop computers, where the slim and inexpensive LCD screens are the best fit. Problems can occur with LCD connections, power sources and backlighting.
  
  

Computer or Monitor?

• If you are confronted with an LCD problem, try to narrow down where it is originating. When dealing with laptops, the problem can be either the screen itself or the computer hardware that is sending the image information, including the video card and the motherboard. Try hooking up an external monitor to the laptop or computer with the questionable LCD screen. If the external monitor shows the image as it should be, then the problem is with the screen itself. If the image is still flawed, the problem is with the computer hardware.
  
  

Check Video Cable Connection

• If the image appears to jump in or out or if all you can see is a white screen, this means that the LCD panel itself is probably working properly and that the image exists but is not being transferred correctly. The problem here lies in the LCD video cable that connects the screen to the video card. Tighten the cable connection and make sure the wires are undamaged.
  
  

Inspect Backlighting

• If you can see the LCD image but it is dark and barely visible, this means that the backlighting has gone out. This is a more common problem with older LCD monitors that use cold cathode (CCFL) lighting, which is not as dependable as the LED lighting in newer models. If you feel confident taking your LCD screen apart, you can usually disassemble the device and correct or replace the lighting, especially CCFL lighting.
  
  

Check the Inverter

• The inverter is a small device that ensures power is passing into the LCD screen. When the inverter is broken, the screen will not work at all. However, you can often replace the inverter and keep using the same screen as before. Inverters are typically behind the LCD panel with the backlighting.