Vizio E70-C3 issue

[NOSValves]

Re: Vizio E70-C3 issue

[QUOTE=dskall;1112229]That voltage is a little low. I don't think it would cause your problem. You might try pulling wire off at tcon-on and apply about 3.4v to pin and see what happens.[/QUOTE.

Thanks, I'll give that a whirl tomorrow. If I can just confirm the panel is okay the boards are pretty reasonable to purchase and real easy to install. I just hate to toss any more money at it without confirming that.

[dskall]

Re: Vizio E70-C3 issue

Removed the board so I could flip it over the NC with 3.4 volt has no trace going any where. Going further I traced the wire from PS board to Main Board and on that end there is a trace that goes to r4018 which in my experience mean a resistor but what's really strange is it looks like the adjacent lead VSNS looks to go to that same r4018... It would seam if that's a common connection it would have to be identical voltage. I guess r doesn't mean what I'm used to...or these traces are so small I'm not seeing what I think I am...

R is resistor. You can always ohm them out to see if they are connected.

[dskall]

Re: Vizio E70-C3 issue

You are correct measuring across the caps netted 376V

That voltage is a little low. I don't think it would cause your problem. You might try pulling wire off at tcon-on and apply about 3.4v to pin and see what happens.

[NOSValves]

Re: Vizio E70-C3 issue

If you are referring to the long caps on hot side of board you have to reference your ground on neg. side of those caps. They should be around 390vdc.

You are correct measuring across the caps netted 376V

[NOSValves]

Re: Vizio E70-C3 issue

Your tcon-on should have about 3.4v on it to turn on tcon 12v to power t-con board. No wires where changed? Is that nc pin on power board indeed have no traces coming off of it?

Removed the board so I could flip it over the NC with 3.4 volt has no trace going any where. Going further I traced the wire from PS board to Main Board and on that end there is a trace that goes to r4018 which in my experience mean a resistor but what's really strange is it looks like the adjacent lead VSNS looks to go to that same r4018... It would seam if that's a common connection it would have to be identical voltage. I guess r doesn't mean what I'm used to...or these traces are so small I'm not seeing what I think I am...

[NOSValves]

Re: Vizio E70-C3 issue

sorry to write bad news.. you probably damaged the panel (screen ) when you take it apart... hopefully not.. but you can disconnect one ribbon cable between the T-CON and the panel at time and turn on see if you will have half screen displayed,

another possibility could happen... you damaged the ribbon cable as they are old enough and dried out easily to bracken the contact pins ( take them out and inspect them carefully with good light source and loop )

Taking one ribbon cable out at a time changed nothing. I inspected the ends of both cables could not find any visual damage. They both seam fine as far as brittleness really don't appear to be dried out. So really only thing suspect I can find is the missing tcon voltage which is also missing on both sides of the tcon fuse.
The high voltage caps I meantioned indeed have 376V on them when measuring across + - sides rather than common chassis ground.

[NOSValves]

Re: Vizio E70-C3 issue

If you are referring to the long caps on hot side of board you have to reference your ground on neg. side of those caps. They should be around 390vdc.

Okay I was using a common chassis ground. I redo that tomorrow also.

[NOSValves]

Re: Vizio E70-C3 issue

Fuse 5A

Thanks! I knew it would be near the 32V 5A stenciled on the board but had no clue which device would be the culprit. I do that test tomorrow.

[NOSValves]

Re: Vizio E70-C3 issue

the panel doesn't have to crack to be damaged, what was on the display is what we needed to know as you were doing that test, it can be confusing but these nice people here can help.

What was on the display? Absolutely nothing....I'm not home so I can not do anymore test just yet! I think these people are great. I don't see what the fuss is about. I'm not an idiot I know it doesn't have to be cracked to be electrically damaged.

Relax I plan to do every test I'm able to do. It's rough when your 12 miles away....

[nomoresonys]

Re: Vizio E70-C3 issue

the panel doesn't have to crack to be damaged, what was on the display is what we needed to know as you were doing that test, it can be confusing but these nice people here can help.

[NOSValves]

Re: Vizio E70-C3 issue

It's hard doing remote troubleshooting, but if you jump around without doing tests, it just makes it that much harder. did you do any of the tests? without feedback how can we help you?

Sorry I'm not home right now so I can't test anything. I previously already unhooked both ribbon cables between tcon and the LCD it didn't change any of the suspect voltages. I'll do any tests mentioned above tomorrow. I'll be surprised if it is the LCD my wife and I were really careful moving it. If it is damaged it will be the address board to LCD that are a little rough getting loose to tape them out of the way to the front. But I guess from what I've read they can be real delicate.

Craig

[nomoresonys]

Re: Vizio E70-C3 issue

It's hard doing remote troubleshooting, but if you jump around without doing tests, it just makes it that much harder. did you do any of the tests? without feedback how can we help you?

[dskall]

Re: Vizio E70-C3 issue

I
Another thing I found is one low voltage electrolytic cap has zero volts and both the 450V caps in the lower left of the power supply board have zero volts. It does not seem logical that a bad panel would cause these things?

If you are referring to the long caps on hot side of board you have to reference your ground on neg. side of those caps. They should be around 390vdc.

[lotas]

Re: Vizio E70-C3 issue

Fuse 5A

[dskall]

Re: Vizio E70-C3 issue

I thought that was strange too. I also wonder about the tcon 12V being 0V and the tcon-ON being 0V....if that board is not turning on how could the display work?
Another thing I found is one low voltage electrolytic cap has zero volts and both the 450V caps in the lower left of the power supply board have zero volts. It does not seem logical that a bad panel would cause these things?

Your tcon-on should have about 3.4v on it to turn on tcon 12v to power t-con board. No wires where changed? Is that nc pin on power board indeed have no traces coming off of it?

[NOSValves]

Re: Vizio E70-C3 issue

not sure maybe check the fuse on tcon, neg probe on chassis ground, pos. probe on each end.

What does this fuse look like?

[NOSValves]

Re: Vizio E70-C3 issue

Your vizio light changes when you power on? Your 3.4v on nc. is puzzling.

Oh and yes the power light works as normal....it also does another strange thing that might give a clue. When you fire it up the led are lighting brite then after like 30 seconds they dim to about half of original. If I hit the V button which would bring up the various built in streaming services they go brite again and stay that way.

[NOSValves]

Re: Vizio E70-C3 issue

Your vizio light changes when you power on? Your 3.4v on nc. is puzzling.

I thought that was strange too. I also wonder about the tcon 12V being 0V and the tcon-ON being 0V....if that board is not turning on how could the display work?
Another thing I found is one low voltage electrolytic cap has zero volts and both the 450V caps in the lower left of the power supply board have zero volts. It does not seem logical that a bad panel would cause these things?

[dskall]

Re: Vizio E70-C3 issue

Your vizio light changes when you power on? Your 3.4v on nc. is puzzling.

[nomoresonys]

Re: Vizio E70-C3 issue

if i recall, i read where they think when the tv is left to run with some leds not working, it may be damaging the panel, see what the test bears out, might be a candidate for the tape cut-off method.