Vizio XVT3D650SV - Help

[newpey]

Hello all,

I am reading and reading but can not seem to find what I need to get my TV working again.

When I plug it in, the Vizio logo glows orange. It then dims a little but stays solid orange. I have no picture and no sound. The TV does not want to turn on at all. I replaced the power board with a tested good one. Nothing changed.

I am GUESSING it is a problem with the main board but not sure. I have a multimeter I just need to be told what to test and I can certainly do that.

Attached are pictures. Thank you guys so much for the help in advance!
~Chris

[newpey]

Re: Vizio XVT3D650SV - Help

pictures!

[bammbammfran]

Re: Vizio XVT3D650SV - Help

probably the main board
Can you post a straight on picture of that board (near the boitom of the board, one part looks burned, but that could be a shadow ??)

[newpey]

Re: Vizio XVT3D650SV - Help

Close ups of main board

[bammbammfran]

Re: Vizio XVT3D650SV - Help

the part that I thought looked iffy in the first picture looks better in the closeups.

The fuse , on the other hand, in the second picture might be blown.
Use your voltage tester and check voltage at the side that is closest to the plug and then check the other side of the fuse.
If power is not going through. Unplug the plug from the power board and if your tester has ohm readings- check the resistance on the outgoing side of the fuse against the ground (pins marked in black) to see if resistance is there or if it shows zero which would mean a short.
There is also a fuse like this on the 4 pin plug that is near this plug that can be checked.

If you do not have power to either side of the fuse, it may not be powered up yet and would have to be checked with just the ohm meter by touching both ends of the fuse . I n this case, you do want to see zero on the reading.

[newpey]

Re: Vizio XVT3D650SV - Help

Thanks for the help! Unfortunately I am getting resistance from the fuse to the left. The fuse on the right is reading at 5 volts on each side. I took a close look at the bottom right of the board and I do not see anything.

I am still stumped

[stj]

Re: Vizio XVT3D650SV - Help

check the voltage regulator in the second foto of your last post.
7805 should have 5v coming out, and over 7v going in.
pinout is printed on the board.

check any others you find too.

[bammbammfran]

Re: Vizio XVT3D650SV - Help

Thanks for the help! Unfortunately I am getting resistance from the fuse to the left. The fuse on the right is reading at 5 volts on each side. I took a close look at the bottom right of the board and I do not see anything.

I am still stumped

You are not supposed to get resistance on a fuse when you check it end for end.
Is there any voltage at that fuse ?

[newpey]

Re: Vizio XVT3D650SV - Help

Sorry I mean it spikes at first then drops to 0

[budm]

Re: Vizio XVT3D650SV - Help

Can you please post clear focused pictures so I can read the labels on the board?

[newpey]

Re: Vizio XVT3D650SV - Help

Closeups round 1... more to come of the other boards..

[newpey]

Re: Vizio XVT3D650SV - Help

Rest of pictures!

[budm]

Re: Vizio XVT3D650SV - Help

So what DC voltage do you get at CN202 PIN 13 (REMOTE_ON/OFF) when TV power switch is activated?

[newpey]

Re: Vizio XVT3D650SV - Help

So what DC voltage do you get at CN202 PIN 13 (REMOTE_ON/OFF) when TV power switch is activated?

If I am hitting pin 13 (I think so) it looks like a solid 5.22 if pressed or not pressed. I checked the other pins as well. The is no change when power button is pressed. If there is 0 volts they stay 0 if there is 5v they stay at 5.

[budm]

Re: Vizio XVT3D650SV - Help

That voltage should toggle high and Low when power switch is toggle, I believe this is the PS_ON signal.

[newpey]

Re: Vizio XVT3D650SV - Help

OK I did some testing on the main board:

The two top fuses where the power comes in..

Fuse on left 5.17 on one side and 5.17 on other
Fuse on right: 0.02 and 0

Voltage Regulator on bottom right (7806cg rka07):
Pins:
Top 5.17
Middle 5.18
Bottom 5.17
Out 5.18

Voltage Regulator on bottom left: (m462 g1117)
Pins:
Top 5.17
Middle 5.16
Bottom 5.17
Out 5.16

Voltage Regulator on middle of board(310fs m540c):
Single pin on each side
In 5.17
Out 4.08

[newpey]

Re: Vizio XVT3D650SV - Help

That voltage should toggle high and Low when power switch is toggle, I believe this is the PS_ON signal.

I double checked each of the pins while pushing the button. No change on any of them

[budm]

Re: Vizio XVT3D650SV - Help

Another fuse should be for the 12V, you can trace that fues and the wire back to the power supply connector, it should end up connected to the 12V out. I do not believe the power supply board is getting the PS_ON signal from the main board to turn on the PFC Voltage booster (the voltage on those three 68uF 450Vdc main filter cap should jump from 160VDC to around 360~400V dc if the PS_ON signal is present), and the 12V power supply section.
So see what DC voltage you have right at the two legs of those 3 caps.
BTW, what do have on the 18V pin of the power supply connector?

[newpey]

Re: Vizio XVT3D650SV - Help

Another fuse should be for the 12V, you can trace that fues and the wire back to the power supply connector, it should end up connected to the 12V out. I do not believe the power supply board is getting the PS_ON signal from the main board to turn on the PFC Voltage booster (the voltage on those three 68uF 450Vdc main filter cap should jump from 160VDC to around 360~400V dc if the PS_ON signal is present), and the 12V power supply section.
So see what DC voltage you have right at the two legs of those 3 caps.
BTW, what do have on the 18V pin of the power supply connector?

Hi there, sorry for my ignorance but I want to make sure I am testing the right stuff.. By the way this forum is awesome. I am so happy you guys are out there trying to help me out!

- The other fuse you are talking about.. are you saying on the main board the fuse that has no voltage is the 12 volt one?

- I am not sure which one is the 18 volt pin? I will do a little more searching with the board in front of me in a sec...


The other thing here.. WHEN the tv was working fine and you plugged it in, the logo would be orange for 5 seconds then would flash white->orange for a good 45-60 seconds. Once it stopped flashing you could then turn it on. In it's current state, when you plug it in the logo remains orange and dims a bit after a few seconds. So I am wondering if the power button being ignored prior to it booting up is normal?

[newpey]

Re: Vizio XVT3D650SV - Help

OK I found the 18v pins.

1 - 0
2 - 0
3 - 5.2
4- 5.2