The LCD TV is currently a widely used television due to its powerful features, which leads to a very high usage frequency, inevitably causing some problems. For example, the LCD TV screen is the most prone to failure, so what to do if the LCD TV has sound but no image? What to do if the LCD TV screen is broken? What are the steps for repairing the LCD TV screen? Let’s take a look.
1. What to Do if the LCD TV Has Sound but No Image
1. If the image gradually becomes blurry until it disappears after turning on, or the image gradually becomes blurry and then returns to normal, it may be a fault in the LCD TV’s computer control.
2. If there is no image when the TV is turned on, many people will try tapping it, and then an image appears. This is suitable for old TVs, as their circuits generally use soldering technology, and the display method is based on cathode ray tubes, which can have poor contact issues that can be resolved by tapping. However, this is not suitable for LCD TVs, and a technician needs to come for further inspection.
3. If the TV displays a snowy picture, it may be a problem with the circuit or the TV signal. If the screen’s colors are overly red or green, for larger TVs, it is mostly a cathode ray tube fault, while for smaller color TVs, it is mostly a color vision discharge circuit problem.
2. What to Do if the LCD TV Screen is Broken
If the LCD TV screen is broken, the repair method depends on the extent of the damage:
1. If the damage is slight and the LCD TV screen can still display normally but has damaged connectors or cables, it can be repaired by replacing the new connectors or re-fixing the cables;
2. If the damage is severe, such as the LCD TV screen being shattered or broken, and the screen cannot display normally, you need to contact the TV’s after-sales service to replace the screen.
The LCD TV’s screen is an important component of the TV, and the cost of replacing a new screen is very high. If the TV has been used for a long time, it is recommended to buy a new one, which is more cost-effective. (Recommended reading: How to Choose a Good LCD TV)
3. Steps for Repairing an LCD TV Screen
1. If the LCD TV screen shows full of noise or vertical stripes, it is generally a problem with the TV buffer board. During the repair of the LCD TV, you can replace a pair of buffer boards, or measure which IC circuit has a fault and replace it accordingly.
2. The LCD TV screen is most likely to show dark bands and lines, which may be caused by the TV overheating, leading to the disconnection of the connection point between the LCD TV’s COF and the screen. In this case, you can use a flat soldering iron with a heat insulation medium to iron it to repair it.
3. If the LCD TV screen lights up when turned on, but after a while there is no light and sound, it is generally due to a fault in the TV screen assembly’s inverter circuit, or it may be due to aging or damage of the TV’s light tube, causing the TV’s high-voltage board to protect itself. During repair, you can use the method of canceling the average feedback from the high-voltage board to the circuit to determine whether the high-voltage board itself has a problem.