Vizio VW46L issue

[sharky]

Ok so I bought this tv. and if you view the picture's you will see my issue.. A few people have told me either the slave inverter board or the lcd controller. any ideas??

When i first turn it on in the morning it will stay half fogged out.. After maybe 30 minutes give or take. I can turn it off. for about 10minutes. and it will flicker. than clear up.. I also noticed if i aim a small fan at the lower left vent after maybe 10 minutes. it will stay clear for hours.. Also sometimes when it starts flickering. the top section flickers separately as in the picture....

[just brew it!]

Looks like you got a defective one. Time to return/exchange it...

[sharky]

I only paid 100 bucks for it.. so i dont mind putting money into it.. just gotta figure out what it is..

Is it over heating??? but it does it the first time i turn the tv on.. so something is going on... If it is a over heating problem I can just wire a internal fan into it.. but that doesn't explain why it does it at first start up int he morning

[just brew it!]

OK, so it sounds like it is thermally related, but not necessarily overheating. Probably a loose connection, bad solder joint, or cracked PCB trace, where thermal expansion/contraction due to temperature changes causes the connection to get better or worse.

If you can run the unit with the PCB exposed, try tapping on components and connectors with a non-conductive (plastic or wood) object to try and isolate the problem area. Be careful, there are high voltages in the backlight inverter!

Assuming you've identified the problem area, try re-seating any nearby connectors or cables as a first step. A bad solder joint may not be practical as a DIY repair if there are a lot of surface mount (especially BGA) components, and if it is a cracked PCB trace you are probably hosed unless the damage is obvious.

If you want to try replacing boards, I have no idea where you would get replacements.

[sharky]

I can get the parts once i figure out which one.. Now I am not a tech. So I am sorry if I ask R-tarded questions.. Please dummyfy some terms for me.. Like PCB.. I did order a new slave inverter to try.. ( 100% returnable if it doesn't fix the issue)... I tried the tapping on the tv, lightly pressing on the screen ( 2 common methods of seeing if its the screen) neither one made a difference. That's when i noticed to me it seemed to be on the hot side out the top vents.. more than likely normal.. So I was just like screw it " hey baby grab me that fan" and just put it on the back on the side that was having the issue . (I am only going into detail above just incase someone else is having a similar issue) I also have a very thin line going threw the almost middle of the screen ( I can deal with it) That is why someone told me maybe the lcd controller, may be causing everything. I will take the back off tomorrow and try to use it with and without the fan. and also try to tapping on things idea. to see what happens

I also forgot to mention.. When I first turn the tv on int he morning the very bottom left corner is white at first than fades away within seconds..

[sharky]

I took the back off. put the stand back on.. hooked up the sat. tv. As soon as i turned it on I noticed the white spot at the bottom was not there.. Also it is not flickering or anything.. It is working perfect.. ( other than that really thin black line) It is not fading out, getting dim, flickering or anything... So what does this mean?

[Captain Ned]

I took the back off. put the stand back on.. hooked up the sat. tv. As soon as i turned it on I noticed the white spot at the bottom was not there.. Also it is not flickering or anything.. It is working perfect.. ( other than that really thin black line) It is not fading out, getting dim, flickering or anything... So what does this mean?

Means that stuff inside was getting too hot.

[sharky]

but it was doing it from the very beginning... Before it gets a chance to heat up

[Captain Ned]

but it was doing it from the very beginning... Before it gets a chance to heat up

Poorly-vented or heat-sinked components can reach their thermal threshold just about instantaneously.

[sharky]

how can I fix that?? Do you know off hand maybe which board it could be?? Would it be the heat sink on the main board?? maybe I can put new thermal paste on it?

[DLHM]

http://www.shopjimmy.com/catalogsearch/result/?q=Vizio+VW46L

This site has alot of parts for that tv, and their pretty cheap.. I might look a the T-Con board. If you can solder and plug/unplug, it could definitely be cheaper.


Edit - After re-reading i would say it's definitely the T-Con board.

[Princess Die]

Poorly-vented or heat-sinked components can reach their thermal threshold just about instantaneously.

Agreed... If you had a can of cold-spray you could chill components near the backlight control sections to see which ones reproduce the problem.

It could be something insidious like a poor solder joint on a ground tab being used to sink heat into the PCB.

[sharky]

Ok so I took the main board out. took off the heat sink. scrapped the heat tape off the cpu and the heat sink.. evenly spread Thermal past ( silver 5). put everything back together.. So far so good.. all issues fixed

[sharky]

Ok so it started doing it again.. I received the new slave inverter board. Did not fix the issue... I took kept the back off and had it turned on.. I went to go spin the tv around and the screen fixed itself.. If I grab either top corner. and kinda give it alittle shake it corrects the issue.. I am assuming now that it is a wiring issue somewhere.. I tried unplugging each of the inverter wires and trying it.. Turing the tv on with any of the plugs undone the tv give no video..

[just brew it!]

If possible, try tapping on internal components (with something non-conductive) while the TV is running. That may help narrow down the location of the bad connection.

[DLHM]

The inverter boards are what start and run the backlighting CCFL (Cold Cathod Fluorescent tube). After viewing you pictures, I don't see any problems thereat all . I will stick to my original idea that it is the T-Con board. Either replace that board or look for bad solder joints,, where I see most are at the back of large components and at the back of the connectors. I would say that this problem is caused by a bad component though... good Luck.

[sharky]

I have tried tapping on stuff with no difference's... Where is the t con board located?? someone else had mentioned it maybe being a bad main board//

[DLHM]

The T-Con is the main board/LCD Controller.

[sharky]

Now I am confused... If you go to shopjimmy or ebay.. They both have t-con boards and main boards offered

T-con
http://cgi.ebay.com/VIZIO-VW46L-HDTV10A ... 56416550ee

Main
http://cgi.ebay.com/VIZIO-VW46L-FHDTV10 ... 56419b6af4

[DLHM]

This is where people need to standardize and call things what they are.. The Ebay board should be called a tuner board or inputs boards, the LCD Controller is the T-Con.. We should call it by function... "main" is not a function.

[sharky]

ok.. so what everyone is calling the main board is nothing more than a tuner/input board.. Ok so where would the main board be located?

[DLHM]

where your inputs attach..

[sharky]

I thought that was just the input/tuner board

OK

So which one do i need to buy??

[matthew66762]

Did you ever figure out how to fix this? If so, please email mattbrooksher@gmail.com

I have the same issue.