# Vizio VW42L Passed Away



## shorteddiode (Apr 6, 2011)

Heard a squeal and set went dead. Vizio logo lights up and changes to white when power button pushed. Removed the back, no bulged caps, no smells, no black spots. Getting correct voltage from power board but do not hear click when power button pushed. Check caps on power board and all have good ESR. Found one 10UF cap on the main board with ESR of 0, all other caps checked good. any ideas, anyone have a copy of the service manual for this set?


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## mechman (Feb 8, 2007)

Could be the panel or the inverter? :huh:


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## shorteddiode (Apr 6, 2011)

Thanks, I was thinking the main boad went out, I haven't tested the transformers on the inverter yet. Was hoping this would be a problem someone had before that could give me soem ideas.


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## United Electronic (Aug 23, 2011)

Check to be certain that you have 24V DC (Main Power) going in to the inverter and, also check for 5V DC (Switch on/off Power) and, sometimes also 3V DC (Brightness control)

IF you have both 24V DC and 5V DC, then it would be the Inverter.

IF you have 24V DC but, NO 5V or 12V DC then I would look toward the Main Board

IF you do not have 24V DC then look toward the Power Supply and, be certain that the Power Supply is putting out the correct voltages

To rule out the Main Board look for the connector that has 5V STB (Standby) and, PSON (Power Supply On) and, use a 1 ohm resistor and short between the 5V and STB (Standby) IF the set lights up but, no picture, then You have some problem with the Main Board

One more thing to check if you have 24V DC coming out of the Power Supply to the Inverter(s) is a Small surface mounted Pico fuse (Usually marked "F"(Fuse) or "S"(safety) and, check for continuity and, if 24V DC is present on both sides

I think I have a Complete Service Manual with flow chart (Diagnostic Chart) for this set. I will look

Jon
United Electronics

Just thought I would return the knowledge I have learned here.

I also have Main Board, Inverters and, Power Supply for this unit as, I have done many of these vizio's

Also please note: Just because a Capacitor is NOT bulged does NOT necessarily mean that it is good. Many times they go bad and LOOK good. Just to help

Hope this helps you


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## shorteddiode (Apr 6, 2011)

Thanks John
I haven't worked on the set in awhile but I will get it out and check the voltages you described and back to you. If you come accross the service manual please le me know. What kinda price do you get for boards?
Thanks
Bob


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## 74f100 (Jul 28, 2011)

You're in good hands here Bob!

See Jon,,, I knew you'd turn into a quality Tech!!!


Jim


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## United Electronic (Aug 23, 2011)

74f100 said:


> You're in good hands here Bob!
> 
> See Jon,,, I knew you'd turn into a quality Tech!!!
> 
> ...


I have learned a ton just reading here

along with prior experiences

I still lack a lot of know how, for the moment But, I will very soon learn

Thanks a bunch to all of you

Jon


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## Raza (Jul 1, 2012)

I have a Vizio WV42L FHDTV10A who has chip blown in the slave inverter. My question are:
- do I have to replace both inverter?
- will the sound back again when the inverter get replaced?
Thanks
Raza


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## 74f100 (Jul 28, 2011)

Raza said:


> I have a Vizio WV42L FHDTV10A who has chip blown in the slave inverter. My question are:
> - do I have to replace both inverter?
> - will the sound back again when the inverter get replaced?
> Thanks
> Raza



The Philips inverters were supposed to be changed as a set (they are the same as the Vizio on many versions). Look on ShopJimmy for the specific part numbers on your inverters. Then see if there is a Philips equivalent and part number that includes both inverters. 

Philips PN example: 9965 000 12345

Then there will be a part number printed on the inverter itself (master will have that printed). 

Inverters will have nothing to do with sound issues, only backlight. The inverters are like a ballast in a florescent house light. They only light the lamps.


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## lcaillo (May 2, 2006)

Why as a set? I seem to recall changing them individually, even just repairing some with the blown ic.


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## 74f100 (Jul 28, 2011)

That's what Philips recommended at the time. 

I've done it both ways, and usually had them back about a year later if only one was changed. There are also rebuild kits available for these inverters. But only if he is familiar with soldering surface mount components.


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## Raza (Jul 1, 2012)

So what's wrong with the sound? they were went out in the same time. Can you help me for that?
Raza


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## 74f100 (Jul 28, 2011)

Sound and backlight are completely un-related. Unless the backlight on pulse from the main is causing the BL failure and not a shorted IC on the inverter.

There are no cause and effect repairs on TV's. Many today think this is how you troubleshoot TV's, they are all wrong. You have to check voltages, perform tests, and isolate the problem. We will do our best to give you basic steps to help YOU isolate the problem. But we can't say with any certainty that no sound = main pcb. Or that no backlight = inverter board. The inverter requires typically 3 voltages. 1. 24v from the power supply
2. BL on (usually around 3.5 to 5 vdc) from the main
3. Dimming pulse (anywhere from 1 to 5 vdc) from the main,,this isn't on all LCD's, but many.

Hope this helps,
Jim


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## lcaillo (May 2, 2006)

The set is likely in protection due to the short on the inverted. You can't assume problems are unrelated without knowing the complete theory of.operation for the design. As said above troubleshooting is needed. 

I differ on the notion that symtom repair is not possible. It is actually the dominant process these days. The lack of documentation, training, and troubleshooting is why many repairs never get completed, however. And why it is hard to find good service.


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## Raza (Jul 1, 2012)

Well,
I checked all voltage from power supply, all voltage are OK in both inverters but in the slave one chip "get fired" with a tiny hole in top of it. So I suppose this is the problem for the pics.
If you guys have a service manual that may help me to diagnose the sound issue.
Thanks

Raza


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## 74f100 (Jul 28, 2011)

To begin troubleshooting a sound issue, first determine if it is on input or all.


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