VIZIO M552i-B2

[budm]

Re: VIZIO M552i-B2

tv plugged in lcd panel connect:
HVDD, .8 mv
VCC, 3.327
VDD, 2.3mv
VGH, -202.4mv
VGL. -5.13
Look for shorted circuit on the tab bonding boards, I.E. capacitor, or COF.
You can first check the resistance between circuit GND and HVDD, VDD, VGH to see which one shows low resistance reading.

[budwich]

Re: VIZIO M552i-B2

oh things just got interesting: ok in reference to me facing the tv from the front:

I removed the tcon board's ribbon to the display right hand side and 3/4 of the right hand screen lit up very brightly and tappers off to the left see picture 1

Then I removed the tcon board's ribbon to the display left hand side and 3/4 of the right hand screen it up dimly in comparison to the first test and has the exact same pattern showing on the screen just dimmer. picture 2

The first picture is somewhat "normal" on the disconnected side (nice white). The bad news is the connected side shows vertical lines which should have been a display of what was being input or maybe blank / black.
The second picture with the opposite cabling shows no "nice white" for the now disconnected tcon to panel cable on that side. :-(

As you have found and probably confirmed with your measurements, there appears to be an issue with the bottom edge driver board on that side. It is not looking good but as budm suggests you might find a edg board component that is replaceable with care to fix the problem.

Further: since you have tried a second tcon, you can see the results are a bit different. The problem for the second card is that disconnecting right side no longer displays a white half screen. From this, I would think that this tcon card has a problem.... if you put back the first card, and repeat the "test" does the screen go back to the initial set of pictures?

[budm]

Re: VIZIO M552i-B2

The T-CON could have been damaged trying to drive shorted circuit.

[ca2014mp2]

Re: VIZIO M552i-B2

tv plugged in lcd panel connect:
HVDD, .8 mv
VCC, 3.327
VDD, 2.3mv
VGH, -202.4mv
VGL. -5.13
Look for shorted circuit on the tab bonding boards, I.E. capacitor, or COF.
You can first check the resistance between circuit GND and HVDD, VDD, VGH to see which one shows low resistance reading.

VDD is shorted and the short is removed when I disconnect the right hand ribbon. All other testing is good. Hvdd vgh are not shorted.

so following the short Im focused on the right hand tab bonding board and the caps are not the same as the left hand side. All the caps on the left tab bonding board are 35uf and on the right tab bonding board I have 5 and I'm getting that they have turned to wires not caps LOL.. the last cap at the far end of the display - the far right hand side is the only one with a reading of 22.49 uf.. I suspect that the short is pulling some of the others down but ill assume they are all bad for now and go for replacement.. the resistors are all good on that tab bonding board. I'll now try to isolate by pulling caps to find my short.. I'll update soon.

[ca2014mp2]

Re: VIZIO M552i-B2

update c192 is a confirmed short on the tab bonding board. and these are not 35uF but 10uF caps

[budwich]

Re: VIZIO M552i-B2

hopefully you can easily replace it and get a working set... yeh!

[ca2014mp2]

Re: VIZIO M552i-B2

yeah, looking for 10uF now. Sourcing my iPhone collection, finally Apple can be worth something.. lol

[budwich]

Re: VIZIO M552i-B2

can you post a picture of the offending area for future reference?

[ca2014mp2]

Re: VIZIO M552i-B2

What do you guys think Im at 30uF of a total of 35uF of capacitance. Do you think harm could be done with firing up the tv with that one cap off the board as I wait for my order to come in.. and BTW where do you guys get your supplies from. I use the usual ebay and amazon and would you mouser more but they have soooooo much there its kinda more difficult to find the exact part.. Let me know your thoughts..
Thanks again and I'll post some good picts by tonight..

[budm]

Re: VIZIO M552i-B2

Is the shorted cap connected in parallel with other caps? Most of the time they are to get more capacitance , if it is then you can fire up for testing.
BTW, those MLCC my be handled with care removing/reinstalling, they cracked easily and shorted out.

[ca2014mp2]

Re: VIZIO M552i-B2

wahhhh whhooo see the pictures..
The screen shot is with the origional t-con board that was able to withstand the short of the 10uF cap on the tab board. So this TV found in the alley was fixed for 50 cents and the help from this board. The cap is on order and will be here in a few days. Soldering was simple short is gone due to bad cap. Tv will be given to my Mr Know-it-all teenage son whom will continue to waste his life away on video games. Much thanks to all..

So I would like to know where you guys get your supplies for repair. let me know.

[budm]

Re: VIZIO M552i-B2

Glad to hear that it is simple cap, you now also know how to go about troubleshooting the problem.
BTW, MLCC failure mode is shorted circuit.
Part suppliers: MOUSER, DIGIKEY, EBAY, misc. spare boards.

[nomoresonys]

Re: VIZIO M552i-B2

Very nice driver board repair, this would have made a good youtube video, if more people knew how to fix their driver boards we could save a whole lot of them from the landfills.

[ca2014mp2]

Re: VIZIO M552i-B2

ok cap is in.. but I still have some lines running vertically from top to bottom on 100% of the screen and spaced consistently ever centermeter. Any thoughts on what might be the cause?

zoom in on picture to see the lines very clearly

[ca2014mp2]

Re: VIZIO M552i-B2

ok cap is in.. but I still have some lines running vertically from top to bottom on 100% of the screen and spaced consistently ever centimeter. Any thoughts on what might be the cause?

zoom in on picture to see the lines very clearly

any thoughts on this issue or should I just start testing all the resistors and caps again on the tab panel?

[budm]

Re: VIZIO M552i-B2

Did you try cleaning and re-seatings the cables between the LCD panel and the T-CON, same for the LVDS cable.
BTW, is this the original T-CON or the replacement T-CON? You have 2 T-CON so do they react the same way?
All the board mounting screws are tightened?

[budwich]

Re: VIZIO M552i-B2

although your picture shows "vertical lining"... it isn't a good method to resolving issues. Get a input of a "standard test pattern" ... color bars or equivalent that is not to busy. this will do two things... provide a test of the frequencies / voltages involved in the signal along with using a signal that is not generated within the main board which may or may not have an issue.

[gregcs]

Re: VIZIO M552i-B2

Anyone ever find a diagram for this model? I'm having a problem with my power supply board - it blew up chip IC 901 (which is an Infineon ice3b1565), which I'm able to find to order. Based on some discoloration on the back of the board, it seems like it may have a problem with part L801 as well, but I can't tell what it is. Looks like some kind of voltage regulator maybe - it's the very upper left part in this image https://www.ebay.com/itm/NEW-Vizio-M...9/114285632480

[viewerau]

Re: VIZIO M552i-B2

ca2014mp2

Can you please tell me what settings to go to, on a multimeter with no beep, to determine whether one of these is faulty or not.

I have a panel that I am advised has/maybe a similar edge board fault, but I do not know how to test it?

Many thanks, and well done on your repair.

[nomoresonys]

Re: VIZIO M552i-B2

Set the meter to diode mode, if you get 000 or close to it it's short, might want to also check those caps for low ohms, expect over 100 ohms on each with meter set to 200 ohms setting, measured the same way with one meter probe on each end.