Yesterday, I repaired a Konka LED24F2210CE LCD TV. The fault phenomenon is: plug in, the panel blue light is on, but all operations (remote control and panel buttons) have no response, no backlight, no image, no sound, just like no boot. Fire Resistant Sleeve,Fireproof Sleeves,Fire Resistant Hose Sleeve,Fire Proof Sleeve Longkou Libo Insulating Material Co.,Ltd. , https://www.liboinsulation.com
Open the cover and check that there are no drum marks and no obvious burn marks on the capacitors of the power supply backlight. Test power supply, 12V, 5V is normal. DIM, ON/OFF is 0V. Prove that the power supply is normal, the main fault range should be on the motherboard, the motherboard number is as follows:
Check the motherboard voltage: 12V, 5V, 3.3V, 1.8V, 1.2V are normal. At this point, the maintenance was deadlocked. Because it is a 24-inch TV, change the motherboard, the cost is too high, the customer will be abandoned. Therefore, the opportunity to study the motherboard failure is lost. Holding the unwilling mentality, I decided to check the circuit outside the microcontroller. The main crystal oscillator (27M) is stable in oscillation frequency. This is suspected to be a problem with the storage part (25Q64). I found the data of the machine on Taobao, took the idea of ​​trying it out, and then purchased the storage IC, burned the data to the IC, and replaced the original storage IC. Boot, everything is OK. At this time, I feel very good. I thought that if I abandon it today, I will lose this valuable maintenance experience. No matter how much money is spent, there is always a sense of accomplishment. I don't know if there is such a feeling about repairing now.
November 26, 2022