LCD screen flickering
Display Configuration A flickering screen may be caused by the computer detecting incorrect display settings as it starts or returns from sleep. It can also come from changes to the screen resolution settings caused by a new program or update installation. Verify screen resolution before assuming the issue is hardware related. Faulty Inverter Next to the display screen behind the plastic screen bezel is a small component called the inverter, which supplies power to the screen backlight. The flickering indicates the power is not reaching the backlight. To fix the issue, replace the inverter. Faulty Connectors The wires and cables traveling from the display around the hinges and into the motherboard tend to wear at the hinge area. Over time, the opening and closing of the screen causes this wear. The solution is to disassemble the plastic casing of the laptop, reorganize the cables so they have no interference from hinges, or replace the cables and connectors with new ones made specifically for the computer make and model experiencing the issue. b> Test an LCD Inverter An inverter is an electrical device on the bottom of your laptop screen. The job of the inverter is to convert DC electrical current to AC voltage to maintain power to the backlight lamp. If the display on your laptop is dark but working, odds are the inverter or the lamp are at fault. When troubleshooting monitor problems on a laptop, you may need to evaluate the inverter to determine which of the two parts is malfunctioning.
Remove the screen bezel on your laptop. The bezel is the piece of the computer casing that surrounds and protects the LCD screen. To remove the bezel, remove the screws around the screen. Bezel removal method may vary by model. Once the screws come out, the bezel should pop off. The inverter will be under the screen. Attach the positive probe (+) of a multimeter to the pin 1 on the inverter. The inverter has two connections, one on each end. With the laptop screen facing you, look at the left side of the inverter. Pin 1 is the top metal flange pointing to the right. Secure the negative probe (-) of the multimeter to any bare screw. There should be a screw securing the inverter to the laptop that will be perfect for the negative ground connection. Turn the laptop on to test the inverter. Turn the multimeter on and check the multimeter reading. If the display records voltage going to the inverter, such as 19 V DC, the inverter power supply is working. Turn the laptop off. Unplug the LCD inverter connection on the right side of the inverter. This disconnects the backlight from the inverter. Plug a working backlight to the connection on the right side of the inverter. Turn on the laptop. If the screen lights up, the backlight lamp is bad but the inverter works. If the screen remains dark, the inverter is bad.
Feb 25, 2013 |
HP Pavilion Computers & Internet