Hardware failure – LCD, inverter, cable or backlight
- The laptop appears to start as usual but the screen is black, if you move it, it turns on and works properly. Failed cable.
- The laptop appears to start as usual but the screen is very dark, although it changes colour a little and you can see a very feint image. Failed inverter or cable 90%/10%.
- Immediately after starting the screen has dark pink/red tint and turns dark after a few seconds. Failed backlight.
- The screen flickers a few times but then turns dark, if you move it or tap it lightly on the sides, it flickers again. Failed cable or LCD 50%/50%.
- Screen is either black or white (no picture) and external monitor works. Failed cable or LCD 30%/70%.
- There are stripes on the screen (either vertical or horizontal) that change when you move the screen or tap it lightly on the sides. Failed cable or LCD 10%/90%.
In all above cases, if you plug in an external monitor, everything shows fine on it (you have to plug it in before starting the laptop and may need to press the “Fn” key together with one of the “F1″ – “F10″ keys to make the laptop recognize the external monitor).
If the screen is black, look for the “lid closed” switch and try pushing it a few times. It’s usually a small switch near the hinges that is pressed when the lid(the screen) is closed. Sometimes these switches get stuck in the “lid closed” position that results in black screen(no backlight) or non-starting laptop. Also some laptops have a magnetic switch (newer Dells, most Macs, etc.) that doesn’t get stuck.
The most common failures are (in this order): inverter, “lid closed” switch, cable, LCD, backlight.