Troubleshooting Laptop Hardware Problems - Hardware Failures: No Display
(Page 3 of 4 )
Now let's discuss what we should do when the laptop seems to be booting up without problems, the hard drive spins appropriately, and we even hear the welcome sound of the operating system, but we have no display on the LCD panel.
The easiest and most foolproof method for testing your LCD screen is to hook up the laptop to an external monitor. If the video output on the external monitor looks fine, this means that the problem is with the video connector, with your LCD panel itself, or with the circuitry that turns on the LCD.
What do we do? It all starts with disassembling the notebook. Find the video connector on the system board (if the video is integrated on the motherboard) or on the video card that is attached to the motherboard. Try re-connecting the cables. You may as well locate the display connector on the back of the end LCD panel. Re-seat that one too. This way you can be sure that the problem is not related to connections.
Every now and then the switch located on the system board that turns the backlight of the LCD on and off can become stuck. If this is the problem then your LCD never powers on. There's a little switch that detects whether the screen of your notebook is open or closed. That's the one we're talking about. Try to push it down and hope it gets unstuck.
Disassembling the laptop to unstick this switch is an option, but sometimes you can get away with not taking it apart. Try lightly hitting that plastic switch. But wait, this isn't the only possible cause, unfortunately. Re-seat the other connectors and cables that are present around the LCD panel and the video on board (including the inverter).
All of the aforementioned can usually be fixed, but let's not forget about the screen itself. Sometimes the screen can become defective. Here we'll enumerate a few scenarios where the screen has gone bad and must be replaced: lots of vertical lines or bands appearing on the screen; half of the screen works fine but the other half stays either black (blank) or really white; the output on the screen looks blurred and changes to different patterns; and so forth. These are almost always signs of a defective LCD panel.
However, if the output on the screen is nothing but garbage, such as incorrectly placed special characters, shadows around the characters, unknown randomly placed marks of different colors, distorted or ugly-looking geometric patterns, or tiny little white dots all over the screen, then these are almost always due to the system board or the connection between the LCD panel and the video card. Re-seat the connectors.
All in all, these are some of the most common hardware failures. Nevertheless, before we finish this part, let's name some of the others that will be covered in the second segment of this guide, along with the promised system instability troubleshooting strategies. These include clicking noises coming from the HDD, which is the well-known symptom of a dying HDD. Thus, back up your important data as soon as possible and order a replacement. Overheating is also discussed thoroughly.
Next: Taking a Break >>
More Hardware Guides Articles
More By Barzan "Tony" Antal
/ 13 
