vizio m220mv red snow

[MiaaZ]

vizio m220mv 2009 and uses a power brick to plug in. I have not found much info on this tv, except reviews.

In this first pic you can see the red snow only in a portion of the screen, I believe it was in standard 4:3 mode, so the portion that was not getting a video signal seemed not to show this effect. (If my thinking is correct)
Second pic is the LVDS portion of the mainboard where I replaced the on 470uf cap and re-flowed the 22uf 16v caps. The 22uf caps I have are half the size of the origonals, so I did not replace those yet.

Visually all the caps look ok, the boards had what appeared to be some white oxidation on the board and some of the solder joints.

I replace a few of the 470uf 16v and 470uf 25v caps by the points where voltage was coming into the board. Some of the red snow went away. Opened it back up and re-flowed quit a few of the joints mainly the caps and connecters for shits and giggles. The ones that I did replace had air pockets under the solder joints and did not flow well at all. Slapped it back together and all the red snow was gone, picture looked beuitiful, UNTIL it ran for about an hour my friends RV. Where he had the heater going. I had tested it in our cool basement and it ran fine.

It only has 2 boards, the main board, and power board, well and the one across the top of the lcd. The power brick I was able to get open somewhat to peak at the caps and they looked ok also, so I didn't tear it apart any further. I didn't test any voltages cause quit frankly I have no clue what they should be, and the mounting of the boards make it near impossible.

I have seen alot of posts that say to change the LVDS cable, but after doing so the symptoms return anyway. reseating helps again for awhile.

Any thoughts on this issue and an area to concentrate on?
thanks

[MiaaZ]

Re: vizio m220mv red snow

And here is the power board. I have a few more of the main board, just trying to get them resized.

[1beertap]

Re: vizio m220mv red snow

It sounds like you probably have bad or failing TCON board.

[MiaaZ]

Re: vizio m220mv red snow

It sounds like you probably have bad or failing TCON board.

22" Razor Class LED-LCD 1080p 60Hz HDTV , 1.75" ultra-slim M220MV

This model does not show a TCON board on vizio's parts list, so I think it is built into the main board. The only other board really is where the 12v plugs into the powerboard.

Which part of the mainboard covers the TCON functions?
These four pics make up the main board.

[mmartell]

Re: vizio m220mv red snow

Where does the cable at the bottom of pic 1 go ? A shot of the back of the set would help us to know the board layout.

[MiaaZ]

Re: vizio m220mv red snow

Where does the cable at the bottom of pic 1 go ? A shot of the back of the set would help us to know the board layout.

It goes to the board that connects at the top of the screen with 6-7 flat copper colored ribbon type connections.


under that metal cover is two more flat white ribbon cables that go from the power board and seem to just connect right into the LCD panel, one at each end of the LCD screen. (black tape on far left top and bottom)

And the cable that is not attached in this pic #3 goes to the power board.

Do these help or do i need to get more pics?

[mmartell]

Re: vizio m220mv red snow

It goes to the board that connects at the top of the screen with 6-7 flat copper colored ribbon type connections.

Well that would normally be your tcon. Is it removeable ?

Wires from the power supply running directly into the panel are usually driving led's so I would guess that's what's going on there.

[MiaaZ]

Re: vizio m220mv red snow

Well that would normally be your tcon. Is it removeable ?

No, it is not from what I can see, looks like it is attached to the screen itself some where.

[tom66]

Re: vizio m220mv red snow

Unplug and reseat that cable going to the "T-con". Do both ends.

[Th3_uN1Qu3]

Re: vizio m220mv red snow

Give it a brush with isopropyl alcohol while you're at it.

[MiaaZ]

Re: vizio m220mv red snow

Unplug and reseat that cable going to the "T-con". Do both ends.

I did that the last time, with the alcohol too, but that was also at the same time I re-flowed some of the solder joints on those main board connections, just not every last one.

And also where the end connects into the board attached to the screen, I pressed the thin metal down onto the connector a little. The other end is a real bear to go on, really requires some preassure.

When I get the TV back later today, I'll do all three again independently to see which had the positive effect on the picture. (If it does again )

While wiggling that cable itself did not change the picture at all, for good or bad. (no tape over connection holding it still)

Neither did squeezing/tapping the panel connections where the ribbon cable goes into the panel itself.

I also tested continuity on the wires all seemed good with the same readings on all of them.