There are images on the screen of household appliances, but the images are covered with noise, flakes, mosaics and other interference. Check the signal source, logic board, LVDS signal, motherboard, screen parameter, LCD screen. The user menu is normal, but the image is flickering. Check the motherboard and scaler chip circuit, repair the chip.
Big picture mode
Big picture mode
Flower screen from time to time, the middle image of flower screen is mixed with many small colorful dots. LVDS patch cord has poor contact.
After the LCD screen is repeatedly powered on, the stripes and colors of the flowers change. Check logic board
After the LCD screen was repeatedly powered on, the stripes and colors of the flowers remained unchanged. The screen itself has a big chance of bad.
There is noise on the LCD screen, and there is noise on the characters. Logic board, screen signal connection, digital board signal output circuit.
The LCD screen characters are normal, and the image has block and dot interference. YPbPr input signal without interference. Input from the AV port again, and the image appears disturbed. The frame memory is soldered, and the image enhancement processing IC control signal line is broken.
The LCD screen images are all dot-shaped, fine broken screens, and characters are normal. Fault in video decoder circuit. This is because faults generated by the image enhancement processing circuit are blocky and not finely broken.
The LCD screen image has distortion or moire. AV test machine everything is normal. Mid- and high-amplification circuits.
LCD screen image regular block flower screen. Communication between motherboard cache and main chip is bad.
The LCD screen has ghosts, and the entire screen has messy colored stripes. Turn off the contrast of the image to judge. If you turn off the contrast, the lack of color in the image indicates that the failure point is the format conversion circuit of the motherboard and the LVDS connection line. On the contrary, if you turn off the contrast, the image is basically normal, indicating that the format of the T-CON board is changed The device does not work properly. The logic board's main screen power supply and chip power supply, the format converter communicates with the frame memory, and the screen memory data is damaged.
When the LCD screen is turned on, an instant screen appears in the upper left. BLON control voltage is abnormal.
The color of the LCD screen image is reversed, and the complementary color appears due to lack of color when the menu display appears. The timing of the interface between the motherboard and the screen is inconsistent. Re-upgrade the corresponding software data.
The LCD screen has color vertical bars, the control function is normal, and there is a black screen phenomenon. The LVDS signal sent by the motherboard does not correspond to the logic timing driven by the logic board. Check the LVDS line and the logic board.
The LCD screen image shows uneven brightness, and there are vertical and horizontal intermittent bright line interference. This phenomenon also exists when other test signals are input. LVDS signal transmission is poor.
Hope the above information is helpful to you.
