Another Vizio VW42L Tv out of the landfill for now.

[ivtec]

Hi guys; a success repair on Vizio VW42L that someone dumped it on the side of the street it started to acting crazy,see video.
http://www.youtube.com/...amp;feature=youtu.be

i disconnected the ty control key pad on the board and re-soldered all pins and it fixed that, but it was hard to control the tv and i did not have the remote control,
also the screen started to flick special if i did lower down the black light adjustment kinda showing random White Black blue red screens to stop it had to shut down
sometimes it would work ok.
then i first started to check the power sup caps all checked ok and checked the Inverter board caps they seem a little bit bulge but they checked good ESR but since i had to order a new remote control so i ordered also 4 - 470uf 35v 105degrees caps,i took out the inverter boards and put in the new caps fairly easy job,closed tv and so far so good tv looks good after 2 hours of working,
note that when i checked the old caps in circuit with my cap-analyzer 88A the ESR was normal,when i tested them out of the circuit they were dead and also tested dead with my Fluke DM, i don't know if it was the heat applied to desoldered them
for now another tv kept ou of the land field,keep my finger crossed.

[Bigjohnga]

Re: Another Vizio VW42L Tv with no 12 volts

I am new to this board, didn't even know it existed until several days ago.
I have been following several threads that are going on in the TV troubleshooting Forum,
and am very impressed with the amount of technical expertise that is evident here.
Now to my question. I have a Vizio Model vw42l unit that I am trying to fix for my son.
When I try to power it up with the power on button, nothing happens. No logo light or back
light. On checking the voltages on the main board, I have no 12v supply. I have checked the
fuses and they are both good. Fuse F1 has 5.17v on both sides, but F2 has 0 volts on both
sides. I do not have a schematic so I dont know where to go from here. Regulator U44 has
no voltage on any pins. Does anyone know where I should start looking? (Sorry about the
photos, I tried three cameras)


Board # 0171-2272-2434

Outputs going to main board:
PSON = 0.00
12V = 0.00
SGND = .00v
5V = 5.17v
A = 0.00
B = 0.00


Inverter Board:
Fuse tested good

Main Board:
Both fuses tested good.
One fuse has 5.17 on both sides of fuse
The other fuse has 2 v on both sides


Voltage Regulators:



U19 Gnd 0.00
Vo 2.51
VI 5.06

1084 Chip

U15 Gnd 2.10
VO 3.36
VI 5.01

1084 Chip

U17 Pin 1 2.08
2 3.33
3 5.08

AMC 1117 Chip

U21 Pin 1 0.00
2 1.25
3 2.50

AMC 1117

U22 Pin 1 2.10
2 3.31
3 5.10

AMC 1117

U44 Pin 1 0.00
2 0.00
3 0.00

117jh 1117L Chip

[budm]

Re: Another Vizio VW42L Tv out of the land field for now.

Did you check for any dcV on the button board?

[Bigjohnga]

Re: Another Vizio VW42L Tv out of the land field for now.

Thank you for your response. I have 3.34 v on the button board.

[Clsc76vette]

Re: Another Vizio VW42L Tv out of the land field for now.

I have a VW42L HDTV10A.
The tv will come on then it starts flashing and has a popping sound.
The tv then goes black/off.
I have the back off and all looks ok,i.e. no buldged buttons, burn marks.
Any ideas where to look?