Vizio VW42L HDTV10A Wont turn on

[Wehan]

I have a Vizio VW42L HDTV10A that my parents gave me because it simply will not turn on anymore (remote or power button) I picked it up from their house and brought it home and plugged it in and it turned on and seemed to work just fine. I left it plugged in and off for about an hour and now it will not turn back on, Vizio logo is amber and nothing happens at all. I am fairly competent with electronics given the proper guidance so where do I start?

[budm]

Re: Vizio VW42L HDTV10A Wont turn on

You can start by upload good clear pictures of the whole back side of the TV, and the board. The power supply board's connectors should have labels for each pin of the connectors, report the DCV reading of each pin and its pin names so we know what they are. We are looking to see what Voltages and signals are there or not when the TV is OFF and when the power switch is activated.

[Wehan]

Re: Vizio VW42L HDTV10A Wont turn on

So you want me to measure DCV off the plugs/pins on the power supply board. Do I do this as it sits plugged in or do you want me to hold down the power button or press it while I measure? or??

[budm]

Re: Vizio VW42L HDTV10A Wont turn on

Everything are all connected back together, plug the TV into the outlet, black probe on the chassis, red probe on each pin, write dow the reading with its name next to the reading, then hit the power switch and let go and take the readings again.
So the board is Vizio 0500-0507-0450 (DPS-260HP A).
http://www.shopjimmy.com/vizio-0500-...er-supply.htm#

[Wehan]

Re: Vizio VW42L HDTV10A Wont turn on

Hope I did this correctly.

[budm]

Re: Vizio VW42L HDTV10A Wont turn on

OK, the main baord is not sending the PS-ON to turn on the 12V/24V, the PFC Voltage booster circuit.
There are two SMD fuses on the main board next to the white connector that the power supply cables are connected to.
More likely the board has bd Voltage regulator IC.
So check the fuses on the main board first, using chassis as the GND ref. for the meter, one of the fuse should have 5VDC on both ends, another will show just about nothing because the 12VDC is not present.
Then you ned to check the Voltage regulator ICs, see this link:
https://www.badcaps.net/forum/showth...999#post300999

[Wehan]

Re: Vizio VW42L HDTV10A Wont turn on

OK I checked these guys and they read 5.12 and 7mv on both ends. I'm working out the Voltage regulators now.

[Wehan]

Re: Vizio VW42L HDTV10A Wont turn on

U3
AZ7805T
-EI
744JK60
7.4mv
.2mv
.2mv

Q27 ? (see pics)
C5886
7x
8.2mv
8.2mv
5.4mv

U2
AMC1117
F0748G
2.06
3.31
5.06

U8
AMC1117
F0748G
2.03
3.28
5.09

U33
AMC1117
F0748G
2.05
3.30
5.06

U7
AMC1117
F0748G
27.7mv
1.26
3.30

U9
K1117S15
744
.3MV
1.49
3.30

U10
1084
0747AL
1.35
2.60 this leg does not connect to the board (see pics)
5.05

[Wehan]

Re: Vizio VW42L HDTV10A Wont turn on

Pics

[budm]

Re: Vizio VW42L HDTV10A Wont turn on

Vref of 1.25VDC + Vdj (pin 1) = Vout pin 2 middle pin.
They look OK, the 7805 is not putting out because the 12VDC in put is not present.

[Wehan]

Re: Vizio VW42L HDTV10A Wont turn on

Ok, so as far as we can tell the voltage regulator ic's are all good?

[budm]

Re: Vizio VW42L HDTV10A Wont turn on

Yes, so the problem is some where on the main board, exactly where I do not know.
You are sure that you found all the regulator IC s?

There are many threads on this model that you should look through them.
https://www.badcaps.net/forum/search...archid=5013580

[Wehan]

Re: Vizio VW42L HDTV10A Wont turn on

Not much help from thoes threads. Yes, I quadruple checked and that is all the ic's unless I'm supposed to be looking elsewhere other than the main board for them.

[budm]

Re: Vizio VW42L HDTV10A Wont turn on

There are many versions of this model.
The main board runs around $60 but there is common failure with the inverter boards also that you have to watch out for, they make the repair kits for them.
http://www.shopjimmy.com/catalogsear...+VW42L+HDTV10A

[Wehan]

Re: Vizio VW42L HDTV10A Wont turn on

Ordered a board, Ill update when I get in in.

[Wehan]

Re: Vizio VW42L HDTV10A Wont turn on

New Board came in today, works great again!!! Thanks!

[budm]

Re: Vizio VW42L HDTV10A Wont turn on

Thanks for the follow-up on the repair. So how much was the replacement board?

[Wehan]

Re: Vizio VW42L HDTV10A Wont turn on

$82.19 to my door. Not bad for a "free TV"