Vizio GV42L HDTV amber light no pic only clicking rapidly

[schwegy]

I need some assistance with my Vizio GV42L HDTV. Once I plug it in, the front logo lights up amber with no picture. I have a clicking noise that does not stop and is continues. I have open the TV up and replaced the 835-1A-B-C 12v R1 relay with no luck.

[tom66]

Re: Vizio GV42L HDTV amber light no pic only clicking rapidly

Is it the relay that is actually clicking? Have you isolated the noise source using precision instrumentation? (sometimes known as a cardboard toilet roll tube)

[schwegy]

Re: Vizio GV42L HDTV amber light no pic only clicking rapidly

I do not have any other testing equipment other then a quality multimeter. I attempted to identify the source of the clicking my simply touching each component in the area. The vibration is the strongest at the relay, but I understand this is not that wise or accurate.

[tom66]

Re: Vizio GV42L HDTV amber light no pic only clicking rapidly

I was joking about precision instrumentation - Just place a cardboard roll against your ear and try and isolate the noise. Works very well. It wouldn't be advisable to touch any mains side components with the TV on, as high voltage may be present there.

[schwegy]

Re: Vizio GV42L HDTV amber light no pic only clicking rapidly

The clicking seems to be coming from the relay and I can hear (using the paper towel tube) a zapping coming from the large capacitor. This capacitor looks good, not swollen. Any ideas?

[tibimakai]

Re: Vizio GV42L HDTV amber light no pic only clicking rapidly

I have just sold one yesterday. On mine it was a black screen with a couple of colored vertical lines and it ended up being the famous U33 regulator on the mainboard.
Maybe the power supply it's at the limit of starting up.
Picked it up for $30 and a half an hour fix( 1x VDO)= $300

[schwegy]

Re: Vizio GV42L HDTV amber light no pic only clicking rapidly

tom66 do you agree with tibimakai that the U33 might be the problem? The thing is I am not getting any picture at all.

[ben7]

Re: Vizio GV42L HDTV amber light no pic only clicking rapidly

tom66 do you agree with tibimakai that the U33 might be the problem? The thing is I am not getting any picture at all.

It might be that the U33 is shorted and preventing the PSU from turning on. Or, it might be that there is a different issue somewhere else.

[schwegy]

Re: Vizio GV42L HDTV amber light no pic only clicking rapidly

I located what I think is the U33. How can I test this? If this is whats bad, this is testing my skills on soldering...

[tom66]

Re: Vizio GV42L HDTV amber light no pic only clicking rapidly

Have you posted a picture of your main board?

[tibimakai]

Re: Vizio GV42L HDTV amber light no pic only clicking rapidly

Your board it's different.

[budm]

Re: Vizio GV42L HDTV amber light no pic only clicking rapidly

The U33 on this board is not the LDO 3-PIN regulator IC like other chassis.
Can we see good clear pictures of the main board?

[tom66]

Re: Vizio GV42L HDTV amber light no pic only clicking rapidly

Here's a nice thread by retiredcaps on how to test regulators:
https://www.badcaps.net/forum/showthread.php?p=266372

[schwegy]

Re: Vizio GV42L HDTV amber light no pic only clicking rapidly

Attached is my TV board.

[Worminizer]

Re: Vizio GV42L HDTV amber light no pic only clicking rapidly

I have a vx42L which looks like it has the same internals as this one. I however don't have any clicking. My vizio emblem glows orange. power button does nothing. If i press the blue button on the bottom left of the main board for about 10 secs, i can then hit power and it will turn the emblem white. This kicks on my 12v, and 24v rails on the power board. I have 24v at both inverter boards plugs. Not sure where to go now. Sorry if you feel I'm hijacking, I will gladly start my own thread. I just figured it was a similar problem on a nearly the same tv. u33 has 5v 3.25v 2.00v on the 3 leads

[tom66]

Re: Vizio GV42L HDTV amber light no pic only clicking rapidly

I have a vx42L which looks like it has the same internals as this one. I however don't have any clicking. My vizio emblem glows orange. power button does nothing. If i press the blue button on the bottom left of the main board for about 10 secs, i can then hit power and it will turn the emblem white. This kicks on my 12v, and 24v rails on the power board. I have 24v at both inverter boards plugs. Not sure where to go now. Sorry if you feel I'm hijacking, I will gladly start my own thread. I just figured it was a similar problem on a nearly the same tv. u33 has 5v 3.25v 2.00v on the 3 leads

See this video: http://www.youtube.com/watch?v=cNFzBJELFoU

[budm]

Re: Vizio GV42L HDTV amber light no pic only clicking rapidly

@schwegy, I can see some 3-pin LDO on the main board. Can you post clear and focused picture of the main board alone?

You can disconnect the top two white connectors that go to the Inverter boards and see if the clicking sound stops.
By the way, where is the relay you replaced located?

[Worminizer]

Re: Vizio GV42L HDTV amber light no pic only clicking rapidly

See this video: http://www.youtube.com/watch?v=cNFzBJELFoU

tom66, I wasn't clear as far as the backlight goes. It has no backlight. The power is to the inverters, but I guess no bl_on signal. I tested the voltage regs that the video suggests, and found two that were off. U2 had 5.14 feed 1.43 adj 2.30 out U9 had 3.25 feed 0.02 adj and 1.5 out . I'm going to check skycraft, its my local military surplus electronic supply house, and if they don't have them, I will order from digikey. I'll let you guys know the results.

Thanks Tom, Nice job!

[tom66]

Re: Vizio GV42L HDTV amber light no pic only clicking rapidly

tom66, I wasn't clear as far as the backlight goes. It has no backlight. The power is to the inverters, but I guess no bl_on signal. I tested the voltage regs that commonly go out on these, and found two that were at least 10% off. I'm going to check skycraft, its my local military surplus electronic supply house, and if they don't have them, I will order from digikey. I'll let you guys know the results.

Thanks

Bad regulators on Vizios can cause a lot of issues. The type of regulator you need is a 1117 type, SOT223 package. Where the device on the motherboard says "-33", "-25", "-ADJ" etc. it's important to match those.

[Worminizer]

Re: Vizio GV42L HDTV amber light no pic only clicking rapidly

I just took a closer look at U9 before I left and its a fixed voltage 1.5, so its fine. Therefore U2 is the only bad one that I have found. I will reply again when I get the new reg.