Hello everyone,
I have an E701-a3 (notoriously risky) that I picked up for $50 with no mainboard (I don't know the backstory very much, the people that sold it weren't too talkative so I don't know much about how it ended up in that state.).
So, bought a replacement board on eBay, hooked it up, and ... TV powered on to lit black screen, but no output on the TV. Did some research, and of course came across the large e701i-a3 thread here: https://www.badcaps.net/forum/showth...t=e701&page=47. I've read that entire thread, and tested the panel for resistance according to the post on page 45 (post #916 I think?).
Came to the conclusion my T-con was toast but the panel seemed ok on the resistance checks (in hindsight, I think my t-con was toast and this test was not accurate). Bought a replacement t-con off of eBay listed as "new"....which was not. Anyway, plugged it in, disconnected the very bottom right (as looking at the tv to watch it) 3/4" ribbon cable, and powered it up. Got some garbled output to the screen for a while, assumed things were in good shape as far as the panel, so hooked it all back up and tried to fire up the TV again. No dice, black illuminated screen only. At that point, never could get the TV to show any sort of image after that while the ebay board was installed, seemingly popped the little transistor.
So, bought a 10-pack of the tiny transistors (COXA) and a better soldering iron. Replaced it on both t-con boards (the original with the TV, and the "new" ebay one). Checked panel resistance with the original board in place, and resistance test clearly showed that the right side of the panel (as viewed to watch TV) was problematic. Powered up the set with that side disconnected, and the T-con seemed to be working somewhat...but distorted/funky.
Decided I was confident enough that the right-side of the panel was my problem point. Drivers on the side ribbon cable/tabs visually looked fine, no obvious burned ones. Peeled off all 5 tabs from the LCD panel to the side driver boards. Hooked everything back up and fired up the set. Now I'm getting bright, evenly illuminated lines on all parts of the TV (not half of the screen, which is good), however it's just a garbled mess.
The attached pictures show as the TV boots up, pressing the menu button, pressing the "Vizio" button to load smart app menu, trying to change the input, etc.
I thoroughly cleaned the t-con ribbon cables as they'd been on and off probably 20 times in troubleshooting over a few weeks. Tried the 'ebay' (now repaired) t-con and it seems totally dead (just the black, illuminated screen).
What should I try next? Do I need to re-repair my t-con? Buy a new (3rd) t-con again? I don't know 100% that my repair on the ebay board was a success, I may remove and re-solder that one (those chips are TINY!).
Looking for any suggestions as to a way to salvage this set if possible. I can send a known test image in to the set if that's helpful. I have a multimiter and soldering iron and 8 more little replacement transistors. Thanks!
I have an E701-a3 (notoriously risky) that I picked up for $50 with no mainboard (I don't know the backstory very much, the people that sold it weren't too talkative so I don't know much about how it ended up in that state.).
So, bought a replacement board on eBay, hooked it up, and ... TV powered on to lit black screen, but no output on the TV. Did some research, and of course came across the large e701i-a3 thread here: https://www.badcaps.net/forum/showth...t=e701&page=47. I've read that entire thread, and tested the panel for resistance according to the post on page 45 (post #916 I think?).
Came to the conclusion my T-con was toast but the panel seemed ok on the resistance checks (in hindsight, I think my t-con was toast and this test was not accurate). Bought a replacement t-con off of eBay listed as "new"....which was not. Anyway, plugged it in, disconnected the very bottom right (as looking at the tv to watch it) 3/4" ribbon cable, and powered it up. Got some garbled output to the screen for a while, assumed things were in good shape as far as the panel, so hooked it all back up and tried to fire up the TV again. No dice, black illuminated screen only. At that point, never could get the TV to show any sort of image after that while the ebay board was installed, seemingly popped the little transistor.
So, bought a 10-pack of the tiny transistors (COXA) and a better soldering iron. Replaced it on both t-con boards (the original with the TV, and the "new" ebay one). Checked panel resistance with the original board in place, and resistance test clearly showed that the right side of the panel (as viewed to watch TV) was problematic. Powered up the set with that side disconnected, and the T-con seemed to be working somewhat...but distorted/funky.
Decided I was confident enough that the right-side of the panel was my problem point. Drivers on the side ribbon cable/tabs visually looked fine, no obvious burned ones. Peeled off all 5 tabs from the LCD panel to the side driver boards. Hooked everything back up and fired up the set. Now I'm getting bright, evenly illuminated lines on all parts of the TV (not half of the screen, which is good), however it's just a garbled mess.
The attached pictures show as the TV boots up, pressing the menu button, pressing the "Vizio" button to load smart app menu, trying to change the input, etc.
I thoroughly cleaned the t-con ribbon cables as they'd been on and off probably 20 times in troubleshooting over a few weeks. Tried the 'ebay' (now repaired) t-con and it seems totally dead (just the black, illuminated screen).
What should I try next? Do I need to re-repair my t-con? Buy a new (3rd) t-con again? I don't know 100% that my repair on the ebay board was a success, I may remove and re-solder that one (those chips are TINY!).
Looking for any suggestions as to a way to salvage this set if possible. I can send a known test image in to the set if that's helpful. I have a multimiter and soldering iron and 8 more little replacement transistors. Thanks!
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