Vizio Powers on no pic or sound

[budm]

Re: Vizio Powers on no pic or sound

You will have to hit the power switch also, if everything else is OK, then you should see pictures on the screen.

[Falcons2677]

Re: Vizio Powers on no pic or sound

screen came on. slightly blurry and discolored but hard to hold resistor in place and hit buttons and look at the screen. What does this tell us? did my measurements from U44 look bad?

[budm]

Re: Vizio Powers on no pic or sound

7805
0723GL
1=10.98
2=0
3=5.02

U44
J303
G9117
1=8.41
2=9.66
3=10.98

They are fine.
7805 is 5V regulator (pin1 Left = Input pin, Center pin/Tab = GND, Right pin = out).

U44 is fine, the ADJ is 8.41V so the output pin (center pin) should be = Adj Voltage + 1.25 Vref = 8.41 +1.25= 9.66V.

Right now we know that the main board is not working due to no PS_ON so I am not surprised that you also not getting pictures due to other section of the circuits are not working either. So you need main board first before going further.

BTW, you can solder the resistor in place, also take the screen shot so we can see what the pictures look like.

[Falcons2677]

Re: Vizio Powers on no pic or sound

I am sure it could be tricky but I would like to try and trace where the problem is on the main board. I will solder resistor in place tomorrow and I will also look for a schematic on the main board. I would also like to thank everyone for their patience and help.

[Falcons2677]

Re: Vizio Powers on no pic or sound

Main Board must be a common problem with this tv. Sold out at most places. I found 1 on ebay for $79. I would really like to try and fix my own though with the help of this forum of coars. I attached some pics of screen.

[budm]

Re: Vizio Powers on no pic or sound

I thought you getting just lines on the screen, but you do have Video on the screen.
Oops, I got your thread mixed up with another VIZIO.
Try reseating the LVDS cable between the main board and the T-CON board.

[Falcons2677]

Re: Vizio Powers on no pic or sound

this is with the PS_ON jumped but I will try reseating cable to clear up the picture.

[budm]

Re: Vizio Powers on no pic or sound

Let me see the pictures of the T-CON board, it looks like it has GAMMA problem.
Do you have other Video source that you can use so I get more ideas what the color really looks like?

[Falcons2677]

Re: Vizio Powers on no pic or sound

Here are 2 pics of the tcon board. 1 pic of the screen. That is a pic of the wii using av plug. I could not get a pic on any of the 3 hd pluggs. Could this all be part of the main board problems? I am still looking around for a breakdown of the main board. I would like to follow the standby voltage to where the PS_ON voltage gets triggered.

[budm]

Re: Vizio Powers on no pic or sound

That looks like bad Gamma problem on the T-CON but not 100% sure unless we check the GAMMA Voltage at the GAMMA Voltage test points which I cannot clearly see on the pictures of the board.