E701i-A3 issue(s)

[vbrad511]

Re: E701i-A3 issue(s)

Second replacement board got here today, but does the same thing. Backlights come on, "V" present, but a bit to the right of the screen, vertical lines all the way across, then lines go away and leave the panel dark. Pressing any buttons on the remote or side control brightens the backlights momentarily, but after a few seconds they drop back down. I've tried blindly changing the input through the remote (with a video source hooked up to hdmi), but can't tell if anything changes, and I get no sound with any of it. I've disconnected the t-con, one cable at a time on it's output side, but still no change. I've done a little reading, and went looking for the panel's ribbon cable on the side, but even after freeing up the plastic frame I'm still not seeing the mentioned cable. Is it under the metal framework? Not sure I'm comfortable trying to get to that, as it's just me here to lift this flimsy, unsupported glass panel. Not sure what to do at this point. Do I wash my hands of this, or convince the owner to throw a t-con or power supply board at it?

[budwich]

Re: E701i-A3 issue(s)

well, you are unlikely to be successful as throwing cards at this particular problem isn't going to resolve the problem as it IS likely a panel problem which takes out a FET on the tcon. You needed to NOT have the tcon to panel cables on the side that gives vertical lines connected (ie. disconnected). this prevents the tcon from dying. Once you get to this point, there are other tests and work that will save the panel and the set. A lot of people with this type of failure replace the component on the tcon (they buy individual fets... "lots") and follow an "isolation" test of disconnecting cables til they get a working picture on one side of the panel... they then remove the bad side tabs on the unconnected side and the tv then works "normally" thereafter.

[nomoresonys]

Re: E701i-A3 issue(s)

Ok, so looks like you need to test the tcon with it hooked up to mainboard BUT NOT to the panel and make sure it's working first, then do the other tests mentioned.

[vbrad511]

Re: E701i-A3 issue(s)

hmmm... you should note that IF there is a panel problem, on vizio's, this type of fault may / usually cause a tcon failure so throwing another tcon at the set is potentially fruitless. Check your cards to see if the "FET" on the board are not shorted / blown. Lots of threads on these large vizios whereby people replace the blown component and do some other testing to determine whether the panel is at fault. IF you get a "good" card, try first having no cables going to the panel connected, power up the set and check voltages at the tcon along with the "known fet". then only plug in one cable, power up and quickly look to see what happens on the display. IF nothing happens (is no display) is less than a few second, pwoer down and potentially save your card from dying. Do the same test, this time with the other only plugged in. Check the display... if you get a good display, then the other side was likely bad. Read some more thread on this type of failure and see if you can save the set.

I appreciate all the help (and patience) from everybody here. Thank you much for sticking it out with me so far.

What is the "FET", and how do I check it? How do I check voltages on the t-con?

[CapLeaker]

Re: E701i-A3 issue(s)

we need a clear, high resolution picture of your tcon board.

[vbrad511]

Re: E701i-A3 issue(s)

[vbrad511]

Re: E701i-A3 issue(s)

I just now got to looking at the pic. That jobber on the left..is that the guy that gets fried when there's a panel fault? Looks like it's had it's better days.

[budwich]

Re: E701i-A3 issue(s)

you probably didn't need to look at the picture to see that ... :-)

what does the other board look like?

Anyway, the board in the picture obviously has a problem. However, it is highly likely that it is a result of a problem elsewhere. The "three legged" things to the left may be "fets" that switch voltages that may have been generated by that "nice chip".... just a guess as I haven't seen a vizio failure up close (worked on a sharp 70 which had similar issues but the sharp tcon has a bit of better design to not "blow up").

Normally, one of the FETs blows as oppose to an IC. the FETs can readily be replaced while that IC isn't easily replaced.

[vbrad511]

Re: E701i-A3 issue(s)

you probably didn't need to look at the picture to see that ... :-)

what does the other board look like?

Anyway, the board in the picture obviously has a problem. However, it is highly likely that it is a result of a problem elsewhere. The "three legged" things to the left may be "fets" that switch voltages that may have been generated by that "nice chip".... just a guess as I haven't seen a vizio failure up close (worked on a sharp 70 which had similar issues but the sharp tcon has a bit of better design to not "blow up").

Normally, one of the FETs blows as oppose to an IC. the FETs can readily be replaced while that IC isn't easily replaced.

Unfortunately, as I'm getting older, I don't see things quite as well as I used to

Are you asking about the main board? The original board that was dead doesn't have anything on it (that I can see) that looks anything like burnt or blown.
Should I plan on a t-con at this point, or are you thinking there's damage further in?
And "three legged things" is about how I need it explained on this

[vbrad511]

Re: E701i-A3 issue(s)

New t-con got here today. I'd really like to test things before I hook it up. Are there voltages I can check, in/out, with my primitive gear, before I hook this one up? Link?

[budwich]

Re: E701i-A3 issue(s)

there is a thread (recent) on doing some resistance measurements that tell if the panel has an issue and what side might be the problem.