vizio VU42FHDTV10A .. no pic or sound

[viziodad]

OK, I checked, and no one here has my exact problem:
Vizio lcd tv .. VU42L FHDTV10A;
No picture or sound..
No 12 or 24VDC. 5VDC is good. ..
Power supply relay clicks when power button on side of tv pressed..
Replaced power supply board ..This one does not even click..
Put old one back in..
PSON pin reads 3.1Vdc..
thank you for any ideas..
I just ordered a main board 'repair kit' off auction site.

[budm]

Re: vizio VU42FHDTV10A .. no pic or sound

If you do have PS_ON and still no 12V or 24V, then we know at least the Main board is sending out the PS_ON signal.
You should verify the dc Voltage right at the two legs of the main DC filter cap when TV is off and when TV is on to find out if the PFC circuit is working or not.
Do you have pictures of the power supply board?

[viziodad]

Re: vizio VU42FHDTV10A .. no pic or sound

Thanks for the quick reply, Budm..Here it is:


http://mail.aol.com/38556-111/aol-6/...il&partIoltage

I will check the voltage on the cap next..

[budm]

Re: vizio VU42FHDTV10A .. no pic or sound

That link does not work for me. Why don't you just upload the pictures?

[viziodad]

Re: vizio VU42FHDTV10A .. no pic or sound

http://mail.aol.com/38556-111/aol-6/...wMail&partId=0

[viziodad]

Re: vizio VU42FHDTV10A .. no pic or sound

My laptop won't copy it..

[budm]

Re: vizio VU42FHDTV10A .. no pic or sound

This is what I get when click on the link:
GAH!
C0FE251E Report ID: 31202-mail-20140508-194825
Service Error
There was a problem handling your request. An unspecified error has occurred.
Try Again

Help and Troubleshooting | Help Pages | Send Feedback

Is this yoUR e-mail address or something?

[vinceroger69]

Re: vizio VU42FHDTV10A .. no pic or sound

https://www.badcaps.net/forum/showthread.php?t=1868

[viziodad]

Re: vizio VU42FHDTV10A .. no pic or sound

100vdc on main cap (on or off)

I'm still working on the photo upload...

[viziodad]

Re: vizio VU42FHDTV10A .. no pic or sound

trying once more

[viziodad]

Re: vizio VU42FHDTV10A .. no pic or sound

thanks Vinceroger69

[budm]

Re: vizio VU42FHDTV10A .. no pic or sound

100vdc on main cap (on or off)

I'm still working on the photo upload...

That cannot be right. Did you measure right at the two legs? When TV is off, it should have around 165~170VDC, and around 370~400VDC when turned on.
Please check your meter's batteries.

[viziodad]

Re: vizio VU42FHDTV10A .. no pic or sound

The large black capacitor at top left near the 2 blue ones?
(Boy, I hate no schematic repairs. Don't know how you guys do it.)
I'll measure it again later when I get home from work, but that's
what I measured last night. I used a metal chassis point, and then
an rca jack for common...

[johnboy1313]

Re: vizio VU42FHDTV10A .. no pic or sound

Measure across the legs of the big cap. Red probe on one leg, black on the other.

[budm]

Re: vizio VU42FHDTV10A .. no pic or sound

If you do have PS_ON and still no 12V or 24V, then we know at least the Main board is sending out the PS_ON signal.
You should verify the dc Voltage right at the two legs of the main DC filter cap when TV is off and when TV is on to find out if the PFC circuit is working or not.
Do you have pictures of the power supply board?

" but that's
what I measured last night. I used a metal chassis point, and then
an rca jack for common..." Please follow my and other people instructions, otherwise it will be difficult to help you troubleshoot the problem due to bad data we receive from you.
You are working in the primary (hot side) of the circuit so the chassis (cold side) cannot be used as the ground ref for voltage measurement in the primary side, the negative leg of the main filter cap is the ground ref for the primary side.

[viziodad]

Re: vizio VU42FHDTV10A .. no pic or sound

Sorry, I should have known that.

Off..cap is 164vdc
On...........164vdc

[budm]

Re: vizio VU42FHDTV10A .. no pic or sound

OK, so the PFC Voltage booster is not working, it has to work so the voltage will be boosted up for the 12V/24V power supply to run. Is this the original board or the replacement board?
What is the P/N as printed on the board or the sticker? DPS-263BP A or DPS-283BP A on that white sticker?

[viziodad]

Re: vizio VU42FHDTV10A .. no pic or sound

Original board..DPS283BP...

[budm]

Re: vizio VU42FHDTV10A .. no pic or sound

OK, Shopjimmy (http://www.shopjimmy.com/media/catal...0005070331.jpg) does not have pictures of the bottom side of the board, we will need to locate the PFC Controller IC and get the P/N so we can look up the spec sheet of the IC and get the pin out.
You will have to provide us with good clear and well focus pictures of the bottom side of the board.

[viziodad]

Re: vizio VU42FHDTV10A .. no pic or sound

Hope ou can see them. ...