LCD TV is a kind of high-tech home appliance product, which also means that once there is a quality problem, maintenance is also a very troublesome thing. The glitches of the LCD TV at home usually include not being able to boot, or there is no sound after booting, or image problems. Below, let’s learn about the LCD TV repair charges and common LCD TV faults and repair methods.
LCD TV repair fee standard
If the LCD TV repair fee does not change the board, the general maintenance fee is 100+, depending on the size of the TV. Replacing the entire motherboard would cost around $300-500. Some generally give vague maintenance cost quotations such as “rear projection TV 400 yuan”, “LCD TV 400 yuan”, “38-inch 250”, etc. There is no standard for LCD TV repair prices. Different places and different masters have different prices. Be careful not to be fooled. The LCD screen is generally 60-70% of the price of the TV. If the 3-year warranty period is over, there is no need to replace it. It is better to buy a new one.
Reminder: Merchants should not charge door-to-door fees for repairs within the after-sales service card period. If the product has passed the free after-sales service card period, the way the merchants charge door-to-door maintenance fees is reasonable. Since the state currently has no mandatory regulations on home appliance maintenance, companies mostly implement their own standards. When consumers accept home appliance repair service, it is best to ask about the items and costs of the repair service, check the price list or price book, and ask for the original replacement parts and detailed repair service bills in order to safeguard their legitimate rights and interests.
Common faults and maintenance of LCD TVs
1. During the use of LCD TVs, if there is a problem that there is no sound and image when the TV is turned on, and the power light of the TV flashes for a while, it becomes a long light, and the TV The TV flashes white light at the moment of turning on the TV. At this time, the failure of the TV should be that the backlight driver board of the TV is damaged, but it is not ruled out that it is caused by a problem with the TV backlight tube.
2. After the TV is turned on, there are three no phenomena, no sound, no image, and the power light does not light up. The cause of this failure should first be a problem with the power supply board, and again it may be caused by the abnormal operation of the CPU part of the TV.
3. The TV cannot be turned on after the light flashes. The fault judgment of this LCD TV should be that the CPU bus of the TV is not working properly or the IC of the LCD TV is in poor contact.
4. When the TV has full screen dots or regular vertical bars on the full screen, it is usually a problem with the buffer board of the TV. At this time, when the LCD TV is repaired , you can replace a pair of buffer boards, or measure which IC line is faulty, and then replace it.
5. The most common problems with LCD TVs are dark bands and lines. When such problems occur on LCD TVs, it can be summed up as a problem with the TV display screen. The reason for this phenomenon may be that the connection point between the COF of the LCD TV and the screen is disengaged due to the high temperature of the TV. At this time, when repairing the LCD TV, you can use a flat-head soldering iron pad to repair it by ironing the insulation medium. .
6. When the LCD TV is turned on, but there is no light and sound after a period of time, it is generally caused by the failure of the inverter circuit of the TV screen component. In addition, it is also caused by the TV The aging or damage of the light pipe of the machine leads to the protection of the high-voltage board of the TV. At this time, when performing maintenance, you can use the method of canceling the feedback of the average value on the high-voltage board to the circuit to determine whether there is a problem with the high-voltage board itself.
Judgment of common faults of LCD TV screen
1. Huaping. Huaping means that the TV screen will still display images and sound, but the images are not complete, and there will be sudden color blocks and other phenomena, making it impossible for people to watch TV normally. Generally, after this situation occurs, you should first check whether the clock output of the motherboard is normal, whether the three-color signal of the motherboard is output to the main chip part of the line is faulty, and whether there is a short circuit in the connection part of the motherboard signal output to the screen.
2. Black screen. Black screen situations are generally more common, including image interference, screen dissatisfaction, etc., which are all black screen phenomena. After the black screen phenomenon appears, firstly check whether the motherboard program is lost, if so, it can be solved by rewriting the program. Then you need to check whether the chip is damaged. If the chip is damaged, you need to replace it with a new chip and rewrite the program.
3. White screen. After the white screen phenomenon occurs, you should first check whether the main board is working normally. You can press the power switch to check whether the indicator light responds. If the indicator light can change color, it means that the main board is working normally.
The method to test whether the main board is normal is as follows: check whether the connection line from the main board signal output to the screen is in good contact; whether the voltage of each operating point of the main board is normal. If the above tests are normal, then it is not the problem of the motherboard, you should check whether the problem of the chip and the CPU.
