Vizio SV320XVT no video no sound

[ruben53]

Checking this tv Vizio SV320XVT for my friend.He told me the tv started with
no video but with sound now when turned on it shows Vizio image and then
black screen but Vizio lights stay white and no sound.It doesn't give chance
to do anything no menu if hit Imput button do nothing.I checked some voltages

CN3 Pin 1-----3.7v with tv ON
Pin 2,3,4--14.2v " "
Pin 5,6,7,8---0v
Pin 9,10,11---6.4v
Pin 12------4.5v
Pin 13------4.5v
Pin 14------7.5v
So what could be the problem,the backlight inverter,the tcon board or the main board?
Thanks for any help.
See attached file

[ruben53]

Re: Vizio SV320XVT no video no sound

Checking this tv Vizio SV320XVT for my friend.He told me the tv started with
no video but with sound now when turned on it shows Vizio image and then
black screen but Vizio lights stay white and no sound.It doesn't give chance
to do anything no menu if hit Imput button do nothing.I checked some voltages

CN3 Pin 1-----3.7v with tv ON
Pin 2,3,4--14.2v " "
Pin 5,6,7,8---0v
Pin 9,10,11---6.4v
Pin 12------4.5v
Pin 13------4.5v
Pin 14------7.5v
So what could be the problem,the backlight inverter,the tcon board or the main board?
Thanks for any help.
See attached file

Hellow any tips?

[budm]

Re: Vizio SV320XVT no video no sound

We need the name of each pin so we can tell what Voltages are not correct.
The picture is also not in focus so I cannot tell where the CN3 is: main board or the power supply board?

[ruben53]

Re: Vizio SV320XVT no video no sound

We need the name of each pin so we can tell what Voltages are not correct.
The picture is also not in focus so I cannot tell where the CN3 is: main board or the power supply board?

Thanks for answer.The CN3 is in the power supply,the names are:

Pin 1= PSON
Pin 2,3,4= 12v
Pin 5,6,7,8= SGND
Pin 9,10,11= 5vSB
Pin 12= A
Pin 13= B
Pin 14= C

Attached new photo

[budm]

Re: Vizio SV320XVT no video no sound

OK, you do have all the command signals, but at this point your meter probably has low batteries so the Voltage readings are showing higher tan normal, you need to check your meter to make sure is OK.

[budm]

Re: Vizio SV320XVT no video no sound

BTW, what is the P/N as printed on that barcode sticker on the power supply board?
Are these your boards?
http://www.shopjimmy.com/catalogsear...Vizio+SV320XVT

Inverter board 24VDC will need to be tested next.

[ruben53]

Re: Vizio SV320XVT no video no sound

BTW, what is the P/N as printed on that barcode sticker on the power supply board?
Are these your boards?
http://www.shopjimmy.com/catalogsear...Vizio+SV320XVT

Inverter board 24VDC will need to be tested next.

You are right the battery of my DMM was low,changed the battery and now readings are 11.8v on 12v pin, 3.2v on pin 1 Pson,5.15v on 5vSB,3.2v on Pin12
and 3.2v on Pin 13 and 5.4v on Pin 14.

The power supply is 0500-0507-0690.

Checked on CN4 of the inverter board and has this readings:
Pin 1,2,3,4,5=24v------reading is 23.4v
Pin 6,7,8,9,10= SGND1
Pin 11=A------reading is 3.2v
Pin 12=B------reading is 3.2v
Pin 12=C------reading is 5.4v

By the way I hit the power button and it turned on end moving the power button it has a menu that I could scroll it but then I turned it off and on but now is doing the same.

[budm]

Re: Vizio SV320XVT no video no sound

OK, good, so you now have all the correct Voltages and command signals to the inverter boards, so next step is for you to remove the metal shield from the inverter boards so you can inspect the fuses and the parts on the inverter boards.
Are you sure that the backlights are not on?

[ruben53]

Re: Vizio SV320XVT no video no sound

OK, good, so you now have all the correct Voltages and command signals to the inverter boards, so next step is for you to remove the metal shield from the inverter boards so you can inspect the fuses and the parts on the inverter boards.
Are you sure that the backlights are not on?

Ok I removed the metal shield and saw only one fuse is OK don't see anything
burned.Checked the voltage at the 2 capacitors is 24.4v.
I don't know how to check if backlights are on,only see the black screen.
When hit power button the screen turns on and show the vizio logo and then
black screen.

[ruben53]

Re: Vizio SV320XVT no video no sound

Ok I removed the metal shield and saw only one fuse is OK don't see anything
burned.Checked the voltage at the 2 capacitors is 24.4v.
I don't know how to check if backlights are on,only see the black screen.
When hit power button the screen turns on and show the vizio logo and then
black screen.

Update,I did the test with a dark room and a flashlight and can see it says
"no signal" so that means the the backlights are on,wright?

If the backlights are on,that means the backlight inverter board is OK ?

[budm]

Re: Vizio SV320XVT no video no sound

It means the panel is working because you can see the text on the screen with flash lights.
If you look at the back of the TV in the dark room, you should see backlights shining through some holes of the back side of the LCD panel, it does not sound like you have backlights otherwise you will not need the flash lights to see the image on the screen.
We need good clear pictures of inverter board.

[ruben53]

Re: Vizio SV320XVT no video no sound

It means the panel is working because you can see the text on the screen with flash lights.
If you look at the back of the TV in the dark room, you should see backlights shining through some holes of the back side of the LCD panel, it does not sound like you have backlights otherwise you will not need the flash lights to see the image on the screen.
We need good clear pictures of inverter board.

OK tomorrow I will take pictures of the inverter board.
I checked on the back of the tv in dark room and cant see any lights.

[ruben53]

Re: Vizio SV320XVT no video no sound

OK tomorrow I will take pictures of the inverter board.
I checked on the back of the tv in dark room and cant see any lights.

Attached picture of the inverter board.

[dick_barton]

Re: Vizio SV320XVT no video no sound

When hit power button the screen turns on and show the vizio logo and then black screen.

Check you have 24V on both sides of the white ceramic fuse marked ?A/65V (can't really read it from the photo)

[ruben53]

Re: Vizio SV320XVT no video no sound

Check you have 24V on both sides of the white ceramic fuse marked ?A/65V (can't really read it from the photo)

Yes it has 24.4v on both sides and on both capacitors.It is 12A/65V

Attached another picture

[budm]

Re: Vizio SV320XVT no video no sound

What dcv do you have on these test pads when TV is turned on?
VBR-A
ON/OFF
VBR-B
STATUS

[dick_barton]

Re: Vizio SV320XVT no video no sound

What is the IC number (OZ9966?)

[vinceroger69]

Re: Vizio SV320XVT no video no sound

post 9 when you say the screen turns on and shows vizio logo i wonder if this set has 2 seconds too black fault maybe a faulty transformer or ccfl tube/wiring

[budm]

Re: Vizio SV320XVT no video no sound

What is the LCD panel P/N? LC320WUD-SBT1???
The STATUS (LAMP STATUS) test pad may give a clue.
Per spec sheet:
Normal : Low (under 0.7V) / Abnormal : High (upper 3.0V)
Agree that it can be the Transformer, CCFL, PWM IC.

http://www.shopjimmy.com/lg-6632l-05...t-inverter.htm

[ruben53]

Re: Vizio SV320XVT no video no sound

What dcv do you have on these test pads when TV is turned on?
VBR-A
ON/OFF
VBR-B
STATUS

VBR-A---0v
ON-OFF--1.6v
VBR-B---3.2v
Status---5.4v