Why don't my laptop backlight doesn't work?

@gettzon first make sure that it really is only your backlight. A simple check for that would be to darken the room and turn the computer on. Then use a flashlight and angle the light at the screen on different areas. you might make out some shadows or see your desktop etc. IF so, you know it is your backlight.

The issue can be the LCD display itself (bad backlight stip) or it can be the backlight circuitry on your motherboard as well as a bad display cable adapter. You will have to check the voltages on the connector and see if you have power coming from your backlight driver. If yes, it is the display, if no it is the motherboard. Then we need to see a couple of GOOD pictures from both sides of the board; large and focused is best. That way we can try and assist you finding the issue with the board.

Get the maintenance and service guide for your computer from here

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