e701i-a3 no picture but backlights

[brando70]

Re: e701i-a3 no picture but backlights

Yes it would appear your right side is toast. The top picture shows your left side works. Leave those alone.

Boom, this is what I needed to hear. Went ahead and tore the right side off and a week later it's still working great! Picture looks back to normal. In the beginning I had some oddities happen, where it would look fine, and then have some odd lines (see pic), but it seems to be working fine now in the last several days. Just want to say thanks again for the help on this place! We'll see how long I prolonged this TV's final end.

A summary of my experience for those of you still trying to diagnose: I ended up going through 3 Tconn boards (1st: original board, 2nd: plugged it all in on replacement board without diagnostic and it died after 30 seconds, 3rd board (they gave me a free replacement ) I went through a process to diagnose and I killed it, and the 4th one is working in the TV now.

If you get a new Tconn (most likely you may want to buy two, but I found some on ebay that shipped quick out of california for 20 bucks each so not bad) . Ideally you should not connect all the connectors to the Tconn and turn your TV on again like it's just going to magically work again. Do a basic voltage check on the inputs to the Tconn if you can as the inputs ribbons to Tconn should be fine to connect and power up unless you have a different issue upstream. On the outputs, only plug in one ribbon at a time to the Tconn output. See yellow lines in the pic below.


The easiest way to assess which LCD driver side is bad (but most likely to blow a Tconn board) is picking one output on the Tconn or the other and turning the tv on (pro tip: plugged into a power strip makes a easy way to use the switch for a quick power off too). I plugged the left Tconn in first and I saw picture, unplugged it and plugged it to the right side. I saw picture and then it died while looking at it. This was the biggest indicator that the right said had failed. This is also why it's useful to have an extra Tconn. I did end up further investigating by installing a new Tconn and disconnecting the ribbon at 2R or 3R (doesn't matter) and assessing the picture on the LCD. See original post with some more pics HERE

Luckily freak was able to diagnose further and confirm my suspicion via pics that the right side looked messed up. Post with additional detail HERE


Access the driver boards (removed already in this pic) by removing like 5 screws to get the metal bracket off. The plastic shroud on the font of the tv doesn't have to come all the way off.


Tear free the driver boards by pulling them to the left in this pic. See THIS VIDEO for a good reference


What you end up with like everyone else if you do it right


Weird lines I got in the beginning after I plugged everything back in. Those vertical lines were visible over large portions of the TV. They did seem to go away after a day..


Looks good now! Woot.


Closeup

[budwich]

Re: e701i-a3 no picture but backlights

I have more FET's, bought several, knew better. Could try re-seating the cable. But the $100,000 question is how many times do you blow a FET after re-seating before you are 100% sure it's not that.

I disconnected the ribbon cable from the side board only, the ribbon cable is still connected to the bottom board. It was easier to disconnect the cable on the side than on the bottom. Question / clarification: You want the other end of the cable disconnected NOT a cable going to the bottom board?

I'll check out the side boards and tabs looking for things that don't look correct.

Any other boards to disconnect / Anything else to try?

Side Question / Note: We don't move the TV around, it sits on it's TV stand. I question the cable just all of a sudden acts up from being improperly seated?! But will admit I have seen many strange things while repairing things over the decades. More than once have taken something apart that didn't work, put it back together without doing anything, it works fine after that.

No problem... my concern would be that it would be bad that you went to the "tear off tabs" when it wasn't that issue. But ultimately, based on your work todate, the "issue" appears to be the side that you are focusing on, so its your call. As you see with the other recent poster in this thread that his set gave a similar "good picture" with the corner cable disconnected (little or no visible defects other than darkness / color distortion) and then his end results (tabs removed) was "great".

[TheRic]

Re: e701i-a3 no picture but backlights

Removed both ends of the bottom left corner cable. Test patterns were the same.

Re-attached both ends of the cable.

Before I fired it up to watch it blow a FET, I decided to disconnected the jumper cable from the two boards on the left. I disconnected from the lower board, so that the jumper cable is out of the equation. I now get lines across the top of the test pattern, see attachments. Not sure if this means anything. I thought I read something in this thread that were the lines are tells you which driver tab is bad? OR does this mean something else is wrong with it?

[budwich]

Re: e701i-a3 no picture but backlights

hmmm ... that was probably a good idea as it isolates the top side edge board from the bottom.... which I assume now you have both corners connected but the top edge board is no longer being powered... only the bottom "half" board is connected.... AND I take it that the FET didn't blow.... which is good also.

This certainly appears to be some thing wrong with the drivers associated with the top half on that side. You might want to try only removing the tab drivers associated with that edge board (2or 3?). You might be OK at that point... although I do believe "early reports" were that all tabs on the "compromised side" had to be removed. I am not sure if that was ever confirmed or that it was possible that only the top needs to be removed (of course, if the bottom half is the problem, then you have no choice).
Anyways, the reason for the lines is that tab driver somewhere around that area is loading the drivers on the other side... in a bad way... don't run like this too much. IF you physically pull the tabs drivers off, the load goes away and also the lines.
Hope that make sense for you. I am thinking you are basically there.

[TheRic]

Re: e701i-a3 no picture but backlights

You are correct that I did NOT blow the FET. Figured I had a 50/50 shot on saving the FET, more like the hassle of soldering one in.

Since the lines are just at the very top, could I just remove the top tab? Thinking then only the Top Right would be doing full duty and the others 1/2 duty. Not sure if it works that way, specially since you commented about early reports about the whole side had to be removed.

Do you know if I will know instantly if I have to remove the whole side, verses it acts up next week after I put everything back together? What is worse case if I don't remove all the tabs, I blow a FET? OR Damage something else? OR just a bad picture?

You have been very helpful!

[budwich]

Re: e701i-a3 no picture but backlights

I have no "knowing" about only removing "one tab" BUT this is tied somewhat into what I mentioned earlier. I suspect you might be one of the first to discover a bad top tab(s).
The problem you face in only removing one tab (how many are on the top edge board???) is that you then need to connect that edge board back into the lower half. HOWEVER, the top edge board is now "compromised" as it is missing a tab driver. "Earlier peoples" had indicated that only removing the "bad tab driver" and hoping to leave the edge boards connected for the rest DID NOT work... but that may be have been because it was the lower ones. The issue is still the same in a way... you need to remove all the tabs associated with upper edge board and also leave it disconnected at the "jumper cable"... in essence totally removing the upper "components" from that side. This may work / appears to work based on your "isolation testing" already.

At least, you may be saving the lower drivers from working "too hard". I don't believe there is anything you can do for the top half. BUT lots of sets out there are still running with completely one side removed.... it is what it is at this point.

[TheRic]

Re: e701i-a3 no picture but backlights

Did some testing / playing.

There are two side boards, the bottom has 2 tabs, the top has 3 tabs.
There are no components on the boards themselves, there is a chip on the the flexible tab. SO I thought if I removed the top tab from the TV AND the board it would not be sending anything bad back. Tried the test pattern, nothing changed.

SO I thought maybe it's the second tab, even though the lines were at the top. I removed 2nd from the top tab from the TV AND the board. Tried the test patterns, nothing changed.

SO I'll remove the third and final tab on the top board, I had just started to peal off the third and final tab on this board, I realized I forgot to attach the jumper cable between the boards. UUGGHHHH!!! So I finished removing the entire top board. Ran the test pattern top half was now mostly fine (along with the right side).

Removed the bottom board, the cable that connects to that board (the one that goes under / around the bottom corner). Ran the test pattern. Everything is fine / back to normal.

Bottom line, you have to remove both boards to fix this problem.

Which I can understand, the TV is seeing 2 sets of tabs in some spots and 1 tab in other. It does not know how to handle that. If it did, it would just compensate when one of the driver tabs goes bad.

Budwich: THANKS for you help, greatly appreciate it!!

Now to put the TV back together and enjoy watching it in my recliner!

[deerdhunter]

Re: e701i-a3 no picture but backlights

Just joined and just finished reading all 36 pages. My vizio e701i-a3e just went blue\black. Where would be the best place to purchase a replacement T-con board?

[obZen]

Re: e701i-a3 no picture but backlights

Just joined and just finished reading all 36 pages. My vizio e701i-a3e just went blue\black. Where would be the best place to purchase a replacement T-con board?

this is exactly my situation. subbed

[TheRic]

Re: e701i-a3 no picture but backlights

Don't know about the best, but I got my T-con Board from ShopJimmy.

[brando70]

Re: e701i-a3 no picture but backlights

I found mine on ebay.. there were a couple vendors selling out of california and they were 20 bucks and came in a couple days.

[deerdhunter]

Re: e701i-a3 no picture but backlights

Thanks guys. I ordered 2 t-cons off ebay. Fried one but was able to make the fix with the second. The left side tab facing the TV was apparently the culprit but had no visible indicators.

[deerdhunter]

Re: e701i-a3 no picture but backlights

Any market for the fried T-Con boards?

[drakar3]

Re: e701i-a3 no picture but backlights

kudos to the Op I just fixed my 70 inch vizio
all steps worked as you stated
I didn't have to change my tcon it was still good
Last step I had to do was clean tcon cables with alcohol .
again thanks to all that contributed to this fix.

[drakar3]

Re: e701i-a3 no picture but backlights

Pic of final fix

[SleepyWakes]

Re: e701i-a3 no picture but backlights

I have unplugged the left white ribbon and still just backlight when I power it up; and then I tried the right white ribbon, and still just backlight. I even tried unplugging them both. I ordered a t-con board to get here in a few days.

For my TV, Vizio said it was purchased after the recall date so best to just buy a new TV. Does this indicate that the side drivers are okay and I just need to install the new t-Con board? I don't want to burn a t-con board without being sure about the side drivers.

Thanks in advance!

[SleepyWakes]

Re: e701i-a3 no picture but backlights

Looks like it is a bad panel for me. I replaced the t-con and now it boots, but the right half of the screen is gone and there's a horizontal bar across the bottom. I guess I should just trash the TV.

[budwich]

Re: e701i-a3 no picture but backlights

do what you want with the panel... whether a "save" can be done is up to whether you provide valid and good information to the forum. When in doubt, post pictures of what you are seeing along with very good descriptions of what they represent. Otherwise, the dumpster is a good option, I guess. :-)

[SleepyWakes]

Re: e701i-a3 no picture but backlights

It sure would be awesome if there was a save. Here's a pic of the picture. I assumed this was a panel issue, but since I don't know what I'm talking about any advice would be wonderful.

[budwich]

Re: e701i-a3 no picture but backlights

ok... so you got the picture part right... now how about some description of what this represents... what cables are connected, what are not. My guess is you have bad tabs on the right side (looking at the picture). You should spend some time and read thru the thread as there is lots of info and you are basically close to a save.