Thanks for offering your assistance with this. I'm an electronics enthusiast with moderate level of competence (have a decent lab with two power supplies, microscope, DSO, hot air, good iron, can competently work at a component level on SMDs, design and solder own PCBs etc). I really enjoying fixing things and learning new stuff so took up a free 58" LED TV and have been googling and watching Youtube videos to see if I can fix this! I am happy to go down to individual component replacement/strip replacement etc - it's all in the name of learning.
The issues are as follows: the left-hand 1/3rd of the screen is black, no image and occasionally has vertical multicoloured lines. The backlight is functioning on the TV and shining a flashlight doesn't show any image.
The circuitry has a power supply unit and a TCON board (CHOT CV580U1)
Voltages measured are as follows:
12Vin - 12.49V
VBo 0.03V
VSS1 7V
RVAA 15V
LVAA 15V
VGHF 7.7V
VGL -8.8V
There are also 1.2V, 3.3V, 12V and 15V DC power rails present.
The TCON board connects to a LEFT and a RIGHT sub-panels. Each sub panel has multiple connections (chip-on-film, I believe) to the panel/LED circuitry. If a third of the screen is not working, then perhaps it is something to do with a short or open circuit 'upstream' of the three COF strips that feed the leftmost third of the board?
I have attempted to unseat and reseat the mainboard -> TCON board ribbon strip and TCON--> sub-panel ribbon strips.
1. How can one tell if it is the LED strips themselves vs another component? I see that these strips are usually arranged horizontally, but my issue is a vertical one. Perhaps I am naively thinking that it is not the actual LEDs?
Any further information or troubleshooting greatly appreciated.
The issues are as follows: the left-hand 1/3rd of the screen is black, no image and occasionally has vertical multicoloured lines. The backlight is functioning on the TV and shining a flashlight doesn't show any image.
The circuitry has a power supply unit and a TCON board (CHOT CV580U1)
Voltages measured are as follows:
12Vin - 12.49V
VBo 0.03V
VSS1 7V
RVAA 15V
LVAA 15V
VGHF 7.7V
VGL -8.8V
There are also 1.2V, 3.3V, 12V and 15V DC power rails present.
The TCON board connects to a LEFT and a RIGHT sub-panels. Each sub panel has multiple connections (chip-on-film, I believe) to the panel/LED circuitry. If a third of the screen is not working, then perhaps it is something to do with a short or open circuit 'upstream' of the three COF strips that feed the leftmost third of the board?
I have attempted to unseat and reseat the mainboard -> TCON board ribbon strip and TCON--> sub-panel ribbon strips.
1. How can one tell if it is the LED strips themselves vs another component? I see that these strips are usually arranged horizontally, but my issue is a vertical one. Perhaps I am naively thinking that it is not the actual LEDs?
Any further information or troubleshooting greatly appreciated.
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