Vizio VW42l wont come on. No 12 volts

[Bigjohnga]

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


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[budm]

Re: Vizio VW42l wont come on. No 12 volts

No PS-ON from the main board to turn on the power supply, A/B for BL-ON and DIM are also missing.
How about uploading good clear pictures of the whole back side of the TV so we can see all the boards and then the pictures of each board?
Is that ALL of the regulator ICs on the main board?