Hi all, I have a cheap LCD with a cheapo brand name "MASTER", it's one of those sets with a single PCB (Motherboard model: tp.s506.pb801) that handles everything. It powers up fine but shows signs that usually indicate a TCON problem (see images) however there is no TCON to troubleshoot, where should I start troubleshooting, on the mainboard? or the LCD's PCB? I tried tapping the thin LCD PCB while it was running and only got a change in video when I tapped a certain IC on the board (see picture below, IC circled in red) and the screen went dark and came back but now it was white instead of having the weird green haze seen in the first picture when I removed my hand, I tried probing the IC with my multimeter and when probing the bottom right pin (from the orientation of the image) to see if there is any voltage on it the whole screen went darker and came back to normal when I stopped probing. I have no clue of what I'm doing really as I've never encountered video issues on a TV, does this indicate anything about the state of the IC? Any ideas? Thanks
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Bad Video on a cheap MASTER LCD TV,Motherboard model: tp.s506.pb801
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Re: Bad Video on a cheap LCD TV
Found something.. the 3v3 rail is shorted to GND through 10 ohms, I disconnected the Main board to make sure the short wasn't coming from there, should I try to inject voltage and see what gets hot? I'm surprised that It shows as 3.3v on my meter even tough it has a 10ohm short on it
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Re: Bad Video on a cheap LCD TV
Update: Injected voltage at the 3v3 rail and felt the NT71710MFG-000 IC get warm with 2Amps going in, I removed the chip and now resistance went from 10 ohms to 15.5kohm and the couple of resistors around the chip which I previously found to be shorted are fine now, no more shorts. Seems like the IC is the cause of the issues, I'll order a replacement and see what happens...
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