Viore 42" LED issue (Not powering on)

[cheapshot]

Hi all. Working on a Viore LED42VF80 TV. Issue is TV has the 5v standby red LED and can switch on fine to green LED but I do not get any backlight at all. I am only seeing 5v supply but no 24v supply at all and no 12v. I have already replaced the power board and this worked for about 10 secs! I saw the Viore logo and input came up. Then I heard a click and TV shut off to standby on its own. So same issue on both power boards. Could my new board be faulty too? Any help would be appreciated. Thanks!

I can post pics if needed here. Same TV as seen in this thread: https://www.badcaps.net/forum/showth...ight=led42vf80

[audiofreak19]

Re: Viore 42" LED issue (Not powering on)

It sounds similar to a EEPROM on a vizio.

[cheapshot]

Re: Viore 42" LED issue (Not powering on)

How would I go about testing this?

[cheapshot]

Re: Viore 42" LED issue (Not powering on)

Any other ideas here? Not sure where to start testing the power board for the 24V. Sorry...

[audiofreak19]

Re: Viore 42" LED issue (Not powering on)

In your first post you said you don't get any backlight and then you replaced the power board and it turned on for like 10 sec and you saw a picture then it turned off and went into standby. So on your first power board would the backlight turn on even for the 10sec. How were you able to see the image if the backlight was not on.

Does it do this every time you turn the tv on. The picture coming up and then tv shutting off and going back into standby. Or is it only after you swap the boards

[cheapshot]

Re: Viore 42" LED issue (Not powering on)

I got the logo and backlights AFTER swapping the power board. It worked for literally 10 secs then TV cut itself off. When I tried to cut it on original issue came back. No backlight and no logo. I only got the logo and backlights that 1 time when the new power board was installed.

[audiofreak19]

Re: Viore 42" LED issue (Not powering on)

I'm goig out on a limb but I think it's something in the main board because due to the other thread it seems as though the main board has the inverter built into it. Which could explain the backlight and then main board explaining 12v. Where is te led plugged into the main board or the power supply?

[audiofreak19]

Re: Viore 42" LED issue (Not powering on)

When you turn the tv on and the backlight goes out. Can you shine a flashlight behind the screen and see any image. This is easiest if hooked up to a video source. Also do this in a dark room.

[cheapshot]

Re: Viore 42" LED issue (Not powering on)

Nope nothing at all. No image.

[audiofreak19]

Re: Viore 42" LED issue (Not powering on)

Ok look at the t con board and check to see if there is any kind of a fuse on the board. Usually labeled F1 F2 ect. If it has one check the voltages on each side of the fuse and report back.

[bwcbob]

Re: Viore 42" LED issue (Not powering on)

Dead unit even with a new power supply, We have found that the problem is inside the LED panel, To be more specific the red B+ wire on the led strips is touching the aluminum ground plane on one or more LED strips, To verify without taking the panel apart just disconnect the 4 sockets and measure for a short across the pins, If shorted then the problem is inside the panel.
Reason of failure is the close manufacturing tolerances, The Plexiglas reflector is to big and the corners right on the top of the solder connections are pushing against the red B+ wire on the left and right strips thus creating a short.