Summary
======
Vizio VW42L FHDTV10A will not power on without unplugging and re-plugging the TV back in several times.
Problem
======
The TV will not always act the same way when it is plugged in to try and get it to start up.
First, I plug the TV in and get the Vizio logo to light up orange. Press the button to turn it on and nothing happens.
I then unplug the TV and wait a few seconds and re-plug it back in. This time when I press the button, the Vizio logo turns white, but no back light comes on. During this time the outputs from the power board are as follows:
[U]Outputs going to inverter board[U]
24v = 24.9v
SGND = .003v
A = .12v
B = .03v
Outputs going to main board
PSON = 3.18v
12v = 11.5v
SGND = .001v
5v = 5.17v
A = .12v
B = .03v
I then unplug the TV for a few seconds and re-plug it in again. This time when I press the button the logo turns white and the back light comes on. I also cannot turn the TV off when just the logo and backlight come on.During this time the only significant changes on the outputs are the A and B outputs.
A = 3.34v
B = 5.01v
I can sometimes get the TV to come on and function properly. I've left it on for a few weeks at a time so as not to have to try and get it to turn on again, lol.
Things Tested
=========
1 - The filter cap. on the PSU showed a voltage of just over 350v.
2 - I could not find any visual evidence of bad caps throughout the whole system.
3 - All fuses tested good. 1 on T-con, 1 on inverter, 2 on main.
4 - I checked the voltages of the regulators on the main board.
Main board regulators
U20
)11
1084
0739AL
Pin 1 = .55v
Pin 2 = 1.79v
Pin 3 = 3.32v
U19
)11
1084
0739AL
Pin 1 = 1.26v
Pin 2 = 2.52v
Pin 3 = 5.07v
U15
)11
1084
0739AL
Pin 1 = 2.09v
Pin 2 = 3.35v
Pin 3 = 5.07v
U22
AMC1117
F0748F
Pin 1 = 2.10v
Pin 2 = 3.36v
Pin 3 = 5.12v
U21
AMC1117
F0748F
Pin 1 = .00v
Pin 2 = 1.26v
Pin 3 = 2.51v
U17
AMC1117
F0748F
Pin 1 = 2.10v
Pin 2 = 3.37v
Pin 3 = 5.07
U44
J302
G9117
Pin 1 = 8.46v
Pin 2 = 9.72v
Pin 3 = 11.42
U16
AZ7805T
-E1
748J13
Pin 1 = 11.41v
Pin 2 = .00v
Pin 3 = 5.01v
I have read many threads of different issues with Vizio TV's. I am looking for ideas on where and what to check. I am not an electrical Wiz, but do know enough to be dangerous, lol. If this TV isn't worth the time or money to repair I'll be bummed because the picture is, or was, very nice. I'm hoping to save it for in my bedroom to replace the 14" tabletop there now.
I have attached pictures of the 4 boards.
Thank you in advance for your help!
======
Vizio VW42L FHDTV10A will not power on without unplugging and re-plugging the TV back in several times.
Problem
======
The TV will not always act the same way when it is plugged in to try and get it to start up.
First, I plug the TV in and get the Vizio logo to light up orange. Press the button to turn it on and nothing happens.
I then unplug the TV and wait a few seconds and re-plug it back in. This time when I press the button, the Vizio logo turns white, but no back light comes on. During this time the outputs from the power board are as follows:
[U]Outputs going to inverter board[U]
24v = 24.9v
SGND = .003v
A = .12v
B = .03v
Outputs going to main board
PSON = 3.18v
12v = 11.5v
SGND = .001v
5v = 5.17v
A = .12v
B = .03v
I then unplug the TV for a few seconds and re-plug it in again. This time when I press the button the logo turns white and the back light comes on. I also cannot turn the TV off when just the logo and backlight come on.During this time the only significant changes on the outputs are the A and B outputs.
A = 3.34v
B = 5.01v
I can sometimes get the TV to come on and function properly. I've left it on for a few weeks at a time so as not to have to try and get it to turn on again, lol.
Things Tested
=========
1 - The filter cap. on the PSU showed a voltage of just over 350v.
2 - I could not find any visual evidence of bad caps throughout the whole system.
3 - All fuses tested good. 1 on T-con, 1 on inverter, 2 on main.
4 - I checked the voltages of the regulators on the main board.
Main board regulators
U20
)11
1084
0739AL
Pin 1 = .55v
Pin 2 = 1.79v
Pin 3 = 3.32v
U19
)11
1084
0739AL
Pin 1 = 1.26v
Pin 2 = 2.52v
Pin 3 = 5.07v
U15
)11
1084
0739AL
Pin 1 = 2.09v
Pin 2 = 3.35v
Pin 3 = 5.07v
U22
AMC1117
F0748F
Pin 1 = 2.10v
Pin 2 = 3.36v
Pin 3 = 5.12v
U21
AMC1117
F0748F
Pin 1 = .00v
Pin 2 = 1.26v
Pin 3 = 2.51v
U17
AMC1117
F0748F
Pin 1 = 2.10v
Pin 2 = 3.37v
Pin 3 = 5.07
U44
J302
G9117
Pin 1 = 8.46v
Pin 2 = 9.72v
Pin 3 = 11.42
U16
AZ7805T
-E1
748J13
Pin 1 = 11.41v
Pin 2 = .00v
Pin 3 = 5.01v
I have read many threads of different issues with Vizio TV's. I am looking for ideas on where and what to check. I am not an electrical Wiz, but do know enough to be dangerous, lol. If this TV isn't worth the time or money to repair I'll be bummed because the picture is, or was, very nice. I'm hoping to save it for in my bedroom to replace the 14" tabletop there now.
I have attached pictures of the 4 boards.
Thank you in advance for your help!
Comment