Vizio - XVT472SV

[jasenpeters]

Make : Vizio
Model Number : XVT472SV
Serial Number : LSPGMAK5301127

---------------------------------------
Symptoms
---------------------------------------
Plugged In - Visio Logo is Amber/Orange
Power On - Visio Logo is White, Back lighting is on, No picture, menu, etc.

---------------------------------------
Module ID's
--------------------------------------
LG Display : LC470WUL (SB)(M3)
Main Logic Board : 0171-2272-2896, 3647-0282-0150(6b)
Power Board : 0500-0507-0710, Delta DPS-286BP
T-CON Board : KLS-470WLTD CI(3)

---------------------------------------
Main Logic Board
--------------------------------------
-- Fuses
F1 - 5.95v
F2 - 14.1v

-- LDO Voltage Regulators (small package)
Chip Package Markings
1st Line: L271
2nd Line: G9117

 Pin  3    2    1
    In  Out/Tab  Adjust  Diff(1-2)
 ---------------------------------------
 U2  5.88  3.81   2.38   1.43
 U4  3.90  1.46   0.00   1.46
 U6 13.95  9.42   7.97   1.45
 U7  5.90  3.83   2.38   1.45

-- Voltage Regulators (large package)
Chip Package Markings
1st Line: L391
2nd Line: G1084

 Tab Up, Left to Right
 Pin  1   2/Tab   3
 -----------------------------
 U3  2.45  3.93  5.97
 U5  2.39  3.87  5.97

---------------------------------------
Power Board
--------------------------------------
-- Voltages at Connectors

 Label  Voltage (DC) Notes
 ------ ------------ --------------------
 A    0.00 / 3.75  Pwr Off / Pwr On
 B    0.00 / 2.95  Pwr Off / Pwr On
 PSON  0.06 / 3.80  Pwr Off / Pwr On
 +5VSB  5.95 / 5.95  Pwr Off / Pwr On
 12V   0.00 / 14.1  Pwr Off / Pwr On
 18V   0.00 / 21.5  Pwr Off / Pwr On
 24V   0.00 / 27.5  Pwr Off / Pwr On
 SGND  0.00
 SGND2  0.00
 SGND3  0.00

---------------------------------------
T-CON Board
--------------------------------------
-- Fuses
F1 - 27.5v
F2 - 27.5v

-- LED D302 is flashing red 1/sec

Other information:
Voltages seemed to creep up higher at about 1mV per second and then level off at about 1 volt above beginning voltage.
For example: +5VSB started at about 5.35v then crept up to about 6.05v over a 10 minute period, then leveled off afterwards.

The Vref on the G9117 LDO's seems a bit high ~1.50v versus standard 1.25v
Voltages at the Power Board, +5VSB, 12, 18, and 24, seem to be a few volts higher as well.

Any ideas?

Thanks in Advance

NOTE: I used the "CODE" keyword to format the Voltage Data

[budm]

Re: Vizio - XVT472SV

You should check your meter's batteries first, the readings are high which tends to mean the battery is low.

[jasenpeters]

Re: Vizio - XVT472SV

I will check the battery for the DVM.
Any idea on the submitted values?
or Should I re-read the voltages?

Symptom: Back light on, no Image, Video, Menu, etc.

[budm]

Re: Vizio - XVT472SV

"or Should I re-read the voltages?" Yes, so far the control Voltages are present, you probably check to see if you do dcv at both ends of the fuse on the t-con board with ref to the chassis GND.
Also up load the pictures of the whole back side of the TV so we can see the board.

[jasenpeters]

Re: Vizio - XVT472SV

Make : Vizio
Model Number : XVT472SV
Serial Number : LSPGMAK5301127

---------------------------------------
Symptoms
---------------------------------------
Plugged In - Visio Logo is Amber/Orange
Power On - Visio Logo is White, Back lighting is on, No picture, menu, etc.

---------------------------------------
Module ID's
--------------------------------------
LG Display : LC470WUL (SB)(M3)
Main Logic Board : 0171-2272-2896, 3647-0282-0150(6b)
Power Board : 0500-0507-0710, Delta DPS-286BP
T-CON Board : KLS-470WLTD CI(3)

---------------------------------------
Main Logic Board
--------------------------------------
-- Fuses

    Pwr Off    Pwr On 
   In  Out   In  Out
F1 - 5.18 5.18  5.14 5.12 <- Diff = 0.02
F2 - 0.0  0.0  12.09 12.09

-- LDO Voltage Regulators (small package)
Chip Package Markings
1st Line: L271
2nd Line: G9117

 Tab Up, Left to Right
 Pin  1     2    3
   Adjust  Out/Tab  In  Diff(1-2)
 ---------------------------------------
 U2  2.06   3.31   5.12 1.25
 U4  0.00   1.25   3.34 1.25
 U6  6.87   8.13   12.08 1.25
 U7  2.04/2.05 3.29   5.08 1.25 <-- Adj Fluctuated

-- Voltage Regulators (large package)
Chip Package Markings
1st Line: L391
2nd Line: G1084

 Tab Up, Left to Right
 Pin  1   2/Tab   3   Diff(1-2)
 -------------------------------------
 U3  2.09  3.34  5.08  1.25
 U5  2.03  3.28  5.08  1.25

---------------------------------------
Power Board
--------------------------------------
-- Voltages at Connectors

 Label  Voltage (DC)   
 ------ ------------------
     Pwr Off  Pwr On
 A    0.00   2.62
 B    0.00   3.26
 PSON   0.0571  12.09/12.10 <- Fluctuated
 +5VSB  5.18   5.18
 12V   0.00   12.10
 18V   0.00   18.22
 24V   0.00   23.60
 SGND   0.00   -0.01
 SGND2  0.00   +0.01
 SGND3  0.00   -0.01

---------------------------------------
T-CON Board
--------------------------------------
-- Fuses

    Pwr Off   Pwr On 
   In  Out  In  Out
F1 - 0.0  0.0  23.50 23.40 <-- Diff = 0.1
F2 - 0.0  0.0  23.40 23.40

-- LED D302 is flashing red 1/sec

Other information:

 Symptom: Back light on, no Image, Video, Menu, etc. 

 Using a fresh battery on the DVM, resulted in better readings.
 All VR's Vref = 1.25v
 Main Board Fuse 1: Difference on In/Out with Pwr On = 0.02v
 Main Board U7: Fluctuates on Adjust = 0.01v
 Power Board PSON: Fluctuates = 0.01v

Thanks in Advance

NOTE: I used the "CODE" keyword to format the Voltage Data

[jasenpeters]

Re: Vizio - XVT472SV

Here is the Rear Side of the TV, all boards visible.

I already included in the earlier post the Main Board, the Power Board and a partial of the TCON board.

Did you want a specific board?

[budm]

Re: Vizio - XVT472SV

The Voltages are fine now with good running meter so you need to check the Voltage on the SMD fuse of the T-CON board next.

'T-CON Board : KLS-470WLTD CI(3)' is NOT T-CON board. It is LED driver board: http://www.shopjimmy.com/vizio-6917l...iver-board.htm
T-CON board is under the metal shield with two cables going to the main board.

http://www.shopjimmy.com/catalogsear...Vizio+XVT472SV

[jasenpeters]

Re: Vizio - XVT472SV

Okay, I understand now.
I'll take a look.

Thanks for the picture.
I found it.

T-CON Board
Fuse 1 : 0.25 / 0.25 In/Out

[budm]

Re: Vizio - XVT472SV

There is a white SMD fuse on the T-CON board.

[jasenpeters]

Re: Vizio - XVT472SV

It is white with gold ends.

[budm]

Re: Vizio - XVT472SV

Yes.

[jasenpeters]

Re: Vizio - XVT472SV

Ok, I read the fuse on the T-CON board:


T-CON Board
Fuse 1 : 0.25v / 0.25v In/Out

Any ideas?
What about the red flashing LED on the LED Driver board, D302?

[budm]

Re: Vizio - XVT472SV

Ok, I read the fuse on the T-CON board:


T-CON Board
Fuse 1 : 0.25v / 0.25v In/Out

Any ideas?
What about the red flashing LED on the LED Driver board, D302?

The readings are done with the TV turned on? If that is the case then the main board is not supplying the DCV to for the T-CON to function.
This is not going to be easy since you will have to trace out which pin is the Voltage supply pin of one of the two connectors that go to the T-CON board fuse, then we need to locate the switched MOSFET that is used as a switch to supply that Voltage to the T-CON.
Picture is provided by SHOPJIMMY.

[jasenpeters]

Re: Vizio - XVT472SV

Yes, power was on. And I too, figured that 0.25v at the fuse would be low.

Any suggestions on what device on the main board supplies that DCV and what voltage value should it be?

Thanks

[budm]

Re: Vizio - XVT472SV

It should have 12VDC to run the T-CON.

[vinceroger69]

Re: Vizio - XVT472SV

on the mainboard picture theres a white connector on the left which has two white fuses it maybe worth checking those to rule them out.

[budm]

Re: Vizio - XVT472SV

on the mainboard picture theres a white connector on the left which has two white fuses it maybe worth checking those to rule them out.

Those are OK, he already checked them, one is for the 5VSTBY VDC, and another one is for the switched 12VDC, he is getting both Voltages.
Too bad the pictures from SHOPJIMMY is not good enough for me to do the reverse engineering.

[vinceroger69]

Re: Vizio - XVT472SV

Its nice you take the time to actually upload the pictures rather than post a link. As you have probably gathered in the uk we cant click on your links as shopjimmys banned us from seeing them. we have to use a web proxy etc and copying and posting your links dont work, so you taking the time to upload pictures helps us in learning too as we can see what your on about etc and the layout.

[jasenpeters]

Re: Vizio - XVT472SV

I'm tracing now, will have results soon, stand by.....with pix of course....

[jasenpeters]

Re: Vizio - XVT472SV

On the T-CON Board:
I traced the F1 Fuse to the CN1 Connector.

From the TOP of the T-CON board the LAND goes from the F1 Fuse to
the first 4 pins of CN1 Connector (See Picture)

These pins correspond to the single (not twisted pair)
wires: Purple, Blue, White, Gray

These wires connect to the Main Board J9 Connector, pins:
2-Blue
4-Purple
6-Gray
8-White

From the TOP of the Main Board the LAND goes from the J9 Connector toward
U1 and U33. However the LAND ends at 4 through holes.
(See Picture)

I researched and find that U1 and U33, both having the same markings:
4953GM <---- 1st Line
938054 <---- 2nd Line

These devices may be:
Duplex P Channel Enhancement Mode Power MOSFET SO-8 Package
(see datasheet attached)

Getting closer