Vizio 32" VO320E Intermittent Issues

[bahowe1]

Re: Vizio 32" VO320E Intermittent Issues

I ohmed out TF1 - still good to go. No resistance.
I went back and made sure of what I 'thought' I saw last night. New facts. When I plug it in, the Vizio starts orange but immediately starts moving to white (without hitting any buttons). I went back to read regulators, they are all giving me the same ON values as initially reported EXCEPT the following ones:
U11
7805CT
RAG930G
.06
0
0
was
12.18
0.01
5.02

U5
L311
G1117
0
0
5.08
was
1.38
2.63
5.04

TU52
EH13A
928K80
0
0
0
was
0
.42
.1

I cannot get any OFF values since it immediately starts turning on.
That give anyone ideas as to where to start again?

[budm]

Re: Vizio 32" VO320E Intermittent Issues

"U11
7805CT
RAG930G
.06
0
0
was
12.18
0.01
5.02"
This one is normal because we do not have 12V from the power supply.

"U5
L311
G1117
0
0
5.08"
This one is dead, it has 5.08V at input but no output. You should check the resistance between ground and pin 1, ground and pin2.

[bahowe1]

Re: Vizio 32" VO320E Intermittent Issues

Ok, I ohmed out U5
Ground to pin 1 = .03
Ground to pin 2 = 0.0
Sanity check, ground to pin 3 = continued to increase.

[budm]

Re: Vizio 32" VO320E Intermittent Issues

OK, the output pin 2 has shorted to Ground. So it can be the IC, the load, the cap. You will have to remove it and check the resistance on that pad of the board again to see if the shorts goes away without the IC in place.
You have to be real careful when removing the IC since there are very small resistors close by. You should cut the legs first, then add solder to the big tab using 40~60W iron with wide tip to remove the IC.
I think you should look into a new main board.

[keeney123]

Re: Vizio 32" VO320E Intermittent Issues

I would agree with BudM about a new main board provided you find where the short is.

[bahowe1]

Re: Vizio 32" VO320E Intermittent Issues

Hey guys - thanks for hanging in here with me!
I removed the IC U5 tonight. I ohmed out the board and got:
pin 1 = .06
pin 2 = 0
pin 3 = increasing resistance

I am not sure if I did anything with this test, but I also put one probe where the tab was, and one on pin 1 on the IC itself and got .04. Is this telling me that both were bad?

What do I try next?
Thanks again
Ben

[budm]

Re: Vizio 32" VO320E Intermittent Issues

So the pin2 pad on the board and ground still shows shorts circuit, same for the IC. that does not sound good at all. To find shorts on the board will be really time consuming and probably impossible for beginner.

[bahowe1]

Re: Vizio 32" VO320E Intermittent Issues

This is certainly my first go-round with this sort of thing, and you guys have been amazingly helpful. If you guys are pretty confident that a new main board will fix my problem, I will start looking into one. From the price of new TVs, it doesn't leave me a lot of margin to replace a board and be incorrect. I don't really need a TV in the first place.
So, are you guys pretty confident a replaced main board will fix me up?
Thank you
Ben

[budm]

Re: Vizio 32" VO320E Intermittent Issues

32" is not worth much, right now we know for sure that you do have main board problem and you can have more than one problem which you will not know until you get the main board working first.

[keeney123]

Re: Vizio 32" VO320E Intermittent Issues

BudM can he at least verify which board the short is on by disconnecting the cables to the other boards?

[bahowe1]

Re: Vizio 32" VO320E Intermittent Issues

Perfect question Keeney123.

[budm]

Re: Vizio 32" VO320E Intermittent Issues

That regulator is on the main board and its output is used to feed the components on the main board, that adjustable regulator is set for output of 2.6V. It is not any other board that caused the output pin to show very very low resistance. You can disconnect all other board and I am sure the shorts will still present.

[rayandmeesh]

Re: Vizio 32" VO320E Intermittent Issues

I am just replying, because it says I have to in order to post my question. Sorry. I am not helpful to you.

[keeney123]

Re: Vizio 32" VO320E Intermittent Issues

So now the question is do you purchase a new main board or while you buying boards do you also purchase a t-con bd with the main bd. So is it worth it? Because we still do not know if the screen is OK. I hate to gamble, always loose. If you had a good fluke meter one could get with-in a inch or two of the short, but you would have to know all the places this line goes to. How this is done is you hold one probe on one place not moving it. With the other probe you start going to the other places that the run goes to. Watch the meter for the lowest reading. Where ever the lowest reading is, is close to the short. To get even closer one would have to strip back the conformal coating so one can ohm the run. Most likely it will be a component as this unit has pass QC. You can only do this with a meter that is as accurate as a fluke 4 to 5 digits. The other thing you could do, if there is not many components that this run goes to then you could start eliminating components by clipping them, but before you clip them make sure you have a source to buy them at. Anyway this is some of what is required for component level repair.

[keeney123]

Re: Vizio 32" VO320E Intermittent Issues

So now the question is do you purchase a new main board or while you buying boards do you also purchase a t-con bd with the main bd. So is it worth it? Because we still do not know if the screen is OK. I hate to gamble, always loose. If you had a good fluke meter one could get with-in a inch or two of the short, but you would have to know all the places this line goes to. How this is done is you hold one probe on one place not moving it. With the other probe you start going to the other places that the run goes to. Watch the meter for the lowest reading. Where ever the lowest reading is, is close to the short. To get even closer one would have to strip back the conformal coating so one can ohm the run. Most likely it will be a component as this unit has pass QC. You can only do this with a meter that is as accurate as a fluke 4 to 5 digits. The other thing you could do, if there is not many components that this run goes to then you could start eliminating components by clipping them, but before you clip them make sure you have a source to buy them at. Anyway this is some of what is required for component level repair.

[bahowe1]

Re: Vizio 32" VO320E Intermittent Issues

Thanks for describing that process - I had no idea. I would say that I don't have the equipment, nor competencies to trace down to that level. So, I guess you guys are thinking there is the possibility that something happened when I was jumping that regulator that could have brought the screen into question? Because after jumping and before whatever happened, I got to see the screen was good for a good few minutes, blue screen, with the 'no signal' hopping around.
I guess I have a couple questions. Are there people on this forum that would have an interest in repairing the board? I'm just exploring all options. Or would it be more cost effective to just buy a new board? I'm seeing around $100 for a board most sites, with Ebay showing boards in the $50 range.
I can't thank you guys enough.

[keeney123]

Re: Vizio 32" VO320E Intermittent Issues

I did not realize you had gotten a no signal on your screen. So this might be worth investing into a new board. I am thinking Shop Jimmy's or TV Tech Parts would be a good place to buy. I would think around $60 including shipping. I do not know of someone who would repair such a board. Problem is one would have to have the schematics and the proper equipment. Like an oscilloscope and logic analyzer and you would have to have a test eprom to send information into the unit so you would know what was being turned on and when and you would have to send this out in one direction so other signals could not interfere. Usually this is now done at the factory because they have all these capabilities and the money for the equipment. Some basic problems still can be fixed out in the field. My impression is that the techs in the field swap out boards. They have a flow chart to tell them what to do and if they follow the flow chart and do not come up with an answer they blame the panel for the problem. Of course many problems are more complex than that. You could get a new main board and that could work for you or it could be more complex than what one can readily tell. I have a TV I fixed by replacing all of the backlights after I had found one that had been bad. After being used for six months by a friend it now has a screen that is flipping. I replaced both t-con and main bds and still have the problem. So one can never tell. I do not think any of this stuff is very reliable. These TV should last at least 10 years.

[bahowe1]

Re: Vizio 32" VO320E Intermittent Issues

I wanted to post the end result of this (long) thread to hopefully help others that may have the same issues. I ended up replacing the main board and everything works just as it is supposed to!
Also, I wanted to post to tell this community 'Thank you'. Thank you especially to BudM and Kenney123, I would not have gotten anywhere without your willingness to teach and coach me along and stay with the thread until the resolution. You guys are doing a wonderful service in helping others, educating people, and also keeping repairable items out of the landfills. Thank you both!

[keeney123]

Re: Vizio 32" VO320E Intermittent Issues

I am glad that it worked out for you. BudM is the expert here I just have a broad knowledge in electronics. I hadn't done a lot of troubleshooting since 1994, but when I started having electronic problems and I turned to the Authorized Service Companies and they continually mis-diagnosed the different problems I decided to help those willing to learn what I can teach them. It seems to me the companies are dumbing down the next generation. I wrote the Vice President of Sony with this information and they called me up the next day. I told him that I could not get a part no for a ccfl tube. He told me that was not their policy and would straighten that out. He did what he said, as I was then able to call their parts department and did get a part number for a screen. I just do not know in this age of computers why we can not get any part numbers for anything. I am still working on trying to get these companies to be able to supply people with the schematics for a reasonable price.