Graphic Changhong LCD TV LT24630X blue light is not turned on troubleshooting - Home Appliances

0805 Blue Light Factory Direct Sales
SMD Aluminum Electrolytic Capacitor
Shenzhen Factory Direct Patch LED 0805 Blue Light 2012 Highlight Blue Light Beads SMD Hair
MOS Power IC Full Range

Model: Changhong LT24630X LCD TV. Failure: The blue light is not turning on. Repair process: I picked up a Changhong LT24630X LCD TV with an issue where the blue light would sometimes turn on, but at other times it wouldn't boot properly and couldn't be used normally. The user mentioned that the TV had been idle for more than a month.

1

The power supply voltages of 12V and 5V were measured and found to be normal.

12V 5V

The voltage at the first pin of the MOSFET power supply was measured as 5V, which was normal.

MOS 1 foot MOS 1 foot

The voltages at pins 5, 6, 7, and 8 of the MOSFET were all measured at 0V, which was abnormal.

MOS 5678 MOS 5678

After shorting the MOSFET, the backlight turned on, but the boot was unstable.

5_copy 1.jpg 5_copy 1.jpg

The two memory chips, 25LC32 and 24C32, were removed and tested using a programmer. The data on the 25LC32 was normal, but the 24C32 was empty. Reprogramming the 24C32 did not work.

7_copy 1.jpg 7_copy 1.jpg

I replaced the 24C32 memory chip (using a DIP package instead of a surface mount) and burned the data downloaded from a forum.

8_copy.jpg 8_copy.jpg

After installation, the TV booted up normally.

9_copy.jpg 9_copy.jpg 9_copy.jpg 10_copy.jpg 10_copy.jpg

Then I entered the factory mode adjustment screen by pressing the mute, menu, and 7217 buttons on the remote control.

11_copy.jpg 11_copy.jpg

The unit was fully reassembled and tested. Everything worked as expected, and the TV now functions correctly without any issues.

Aluminum Conductor Steel Reinforced

Aluminum Conductor Steel Reinforced,Acsr Conductor,Acsr Wire,Acsr Cable

HENAN QIFAN ELECTRIC CO., LTD. , https://www.hnqifancable.com

Posted on