Vizio VW42lHDTV10A no pix, no sound, won't turn off

[mu2]

Hi,

I've got a Vizio VW42lHDTV10A that when powered on the Vizio logo changes from amber to white and the backlights come up - it has a gray screen. There is no picture, no sound, no menus, etc. - it won't shut off with either the remote or the buttons on the side. Inverters seem to work.
I've checked caps on the power board and main board - nothing puffed. I have checked the caps with an esr meter (both boards) - pulled and tested some with a capacitance meter - all seem to be fine. I replaced some since they were a bad brand with low esr caps (panasonic fm) that I had in stock. Nothing changed the symptoms. All the voltages on the power board check ok (5,12,24) fuses on the t-con, main board check ok. The 5 volt regulator on the main board checks ok.
I've cleaned the connector to the t-con board and reseated it (and the others). If I push the reset button on the main board it will shut the tv off.
I noticed that there are five ic's on the main board that appear to be fixed low dropout regulators - four are marked AMC 1117 and one marked K1117. Does anyone know what the correct voltages should be at these items (U2,U8,U33,U7) and U9? The main board is Vizio 3642-0242-0150
Judging from some internet postings this problem seems to be fairly common - does anyone know the solution?

Thanks,
Mike

[VIZIOTV1234]

Re: Vizio VW42lHDTV10A no pix, no sound, won't turn off

Did you ever solve your problem?

I just happen to have the same problem. Please respond

Thanks

[mu2]

Re: Vizio VW42lHDTV10A no pix, no sound, won't turn off

As a matter of fact, I just fixed the set last week.
I downloaded a service manual from the site in Poland that PlainBill likes.
They didn't have correct one uploaded but I used some information from the VW32LHDTV10A manual. The main boards are similar (not identical!!!)
My suggestion is that if the power supply board is good and the backlights come up then look at the main board.
Use the flow chart trouble shooting chart for the DC -DC converter (Page 9-5).
The defective part in my set was U33 - a LDO adjustable regulator. The output was about 2.07 volts and should have been 3.3 volts.
Good luck.

Mike

[kpswish]

Re: Vizio VW42lHDTV10A no pix, no sound, won't turn off

Hello! My Vizio VW42lHDTV10A died a few days ago and has the same exact issue yours did. After reading your updated post, I went in and checked U33 and found it at 2.13v. Could you tell me where you were able to find a replacement LDO adjustable regulator? I looked up vizio part# 0430-6009-1051 on Google but was unable to find anything other than Sears, but their site says to call for availability.

Kevin

[PlainBill]

Re: Vizio VW42lHDTV10A no pix, no sound, won't turn off

Hello! My Vizio VW42lHDTV10A died a few days ago and has the same exact issue yours did. After reading your updated post, I went in and checked U33 and found it at 2.13v. Could you tell me where you were able to find a replacement LDO adjustable regulator? I looked up vizio part# 0430-6009-1051 on Google but was unable to find anything other than Sears, but their site says to call for availability.

Kevin

LDO regulators are 'jelly bean' parts - available from a number of different manufacturers. If you post the part number of U33 (a picture might help) we can identify the exact version you have and suggest a source. It also would help if you would let us know what country you live in; it makes identifying a source much easier.

PlainBill

[mu2]

Re: Vizio VW42lHDTV10A no pix, no sound, won't turn off

Hi,

I just wanted to let everyone know the part number that I used in repairing my Vizio.
I purchased the part from Digikey. Their part number was 497-1229-1-ND
Manufacturer's part number is LD1117ASTR.
Keep in mind that just because this part fixed my set I can't say that this a common fault. I found it after checking other regulators and parts, usually finding a data sheet on the part and trying to understand how it is used in the circuit.
Good luck!

Mike

[PlainBill]

Re: Vizio VW42lHDTV10A no pix, no sound, won't turn off

Hi,

I just wanted to let everyone know the part number that I used in repairing my Vizio.
I purchased the part from Digikey. Their part number was 497-1229-1-ND
Manufacturer's part number is LD1117ASTR.
Keep in mind that just because this part fixed my set I can't say that this a common fault. I found it after checking other regulators and parts, usually finding a data sheet on the part and trying to understand how it is used in the circuit.
Good luck!

Mike

Actually, that part does appear to be a common problem.

PlainBill

[dossman]

Re: Vizio VW42lHDTV10A no pix, no sound, won't turn off

I'm also working on a Visio and the model is VX42LHDTV10A and it also turns on and the Visio logo goes from amber to white, no backlight screen or sound, will not turn off with remote. I removed both the power supply and the mainbaord to inspect for burned parts and test the fuses, after I re-installed the boards the backlight failed to come on (it did before I removed the boards for testing). Last thing I did was check the power going into the main board and I get 3.1 volts on pin 1, three other pins get 5 volts but there is no 12 volts coming into the board. I downloaded the manual from a link on this site but it is for a L42HDTV10A so being not exactly the same model the J7 pinout shows 14 connections where my set only has 13. Can the mainboard cause the power supply to stop providing 12 volts is my question, and a couple of the 680uF caps on the power supply look a little different on the tops than the other ones. I went to digikey but I do not know exactly what replacement cap I should get. I sure would like to get this set working because my TV is very old and is starting to shows signs of dying. Thanks for any help on this project.

[PlainBill]

Re: Vizio VW42lHDTV10A no pix, no sound, won't turn off

I'm also working on a Visio and the model is VX42LHDTV10A and it also turns on and the Visio logo goes from amber to white, no backlight screen or sound, will not turn off with remote. I removed both the power supply and the mainbaord to inspect for burned parts and test the fuses, after I re-installed the boards the backlight failed to come on (it did before I removed the boards for testing). Last thing I did was check the power going into the main board and I get 3.1 volts on pin 1, three other pins get 5 volts but there is no 12 volts coming into the board. I downloaded the manual from a link on this site but it is for a L42HDTV10A so being not exactly the same model the J7 pinout shows 14 connections where my set only has 13. Can the mainboard cause the power supply to stop providing 12 volts is my question, and a couple of the 680uF caps on the power supply look a little different on the tops than the other ones. I sure would like to get this set working because my TV is very old and is starting to shows signs of dying. Thanks for any help on this project.

Most power supplies used in TVs have labels indicating the proper output voltage on the connectors. The supply is usually a dual supply - a standby supply that is always on, and a main supply that is switched on when the TV is turned on. A good troubleshooting technique is to verify the main supply is turned on, then verify output voltages of the power supply are correct before advancing to troubleshooting the main board.

The symptoms you are describing are similar to those described by others with Vizio TVs. It was due to failure of a voltage regulator (U33) on the main board.

When I hear complaints of "I went to digikey but I do not know exactly what replacement cap I should get" I know someone isn't doing his homework. The question has been asked so many times I even include pointers in my signature. Note that my signature also include suggestions for providing pictures.

PlainBill

[dossman]

Re: Vizio VW42lHDTV10A no pix, no sound, won't turn off

Well I got my backlight to come on again, it was my fault as I had the connector plugged in but off by one pin (too early in the morning or late at night, I can never win), the good news is that now I'm getting good voltages to the mainboard and I can move on to troubleshooting using the manual which only has mainboard troubleshooting in it. After following the flowchart I found some chips that were out of spec and three that were not even on the board or disconnected. With the power switch on part U7 pin2 was 1.07 and should have been 1.8, part U10 pin2 was 2.66 and should be 1.8 but this pin 2 has me confused as it is not connected to the board. The flowchart does not say to check part U33 but after reading the posts I did anyway and got 2.11 volts on pin2. The manual lis for a model GV42L and lists U33 as IC SWITCH P15C3257QE QSOP 16pin LF but on my VX42L it is a AP1117E18LA SOT-223 which only has 4 pins. So I'm still looking for the correct manual before I order any parts. I make mistakes and I'm getting older but I try to fix my errors and double-check my work. Thanks for all the help and good luck with your repairs.

[cadiman]

Re: Vizio VW42lHDTV10A no pix, no sound, won't turn off

On the vx model you might want to look at U9. It should be a k1117s15 I have one that is burned a bit. Tv powers on with backlight and will not power off, no audio, typical for the u33 symptoms failure talked about.

[dossman]

Re: Vizio VW42lHDTV10A no pix, no sound, won't turn off

Looked up k1117s15 on the digikey site and got nothing, I wonder if it can be replaced with this one?

http://search.digikey.com/scripts/Dk...=497-1244-2-ND

[kingofcoins]

Re: Vizio VW42lHDTV10A no pix, no sound, won't turn off

Make sure you are checking the leg voltage pairs correctly, see my 'treatise' thread on the right way and wrong way to do it...post #95 gives summary:
https://www.badcaps.net/forum/showth...t=12766&page=5
The parts nos do indicate the key factor on these LDO's so the k1117s15 part has a typical 1.5V dropout...your 497-1244-2-ND is only rated at 1.1V ..also suggest output be 1Amp or better. My U9 had a 1.5 dropout, and btw it is one of the few on set fixed, most are adjustables.
My set had no U4 LDO , and U5 was an 8 leg IC, so check my attached pic for comparison with yours, and you will also see 'missing' caps in same area of board.
My set had bad U7 and U33 both adjustable LDO's and I used digikey no 497-1229-1-ND which will also replace several AMC 1117 found in these.
Dan

[dossman]

Re: Vizio VW42lHDTV10A no pix, no sound, won't turn off

Is that U9 similar to the U33 and U7 chips? I could find nothing when I searched Digikey for k1117s1, I even tried searching just k117 and still got nothing on their site.

[PlainBill]

Re: Vizio VW42lHDTV10A no pix, no sound, won't turn off

Is that U9 similar to the U33 and U7 chips? I could find nothing when I searched Digikey for k1117s1, I even tried searching just k117 and still got nothing on their site.

The first one or two letters are unique to the manufacturer. K1117 and AS1117 are functionally identical, but from different manufacturers. Digikey's ZLDO1117GDICT-ND and AP1117EGDICT-ND are two parts that would work.

Lecture time. To locate them on Digikey, enter the keyword Voltage Regulator and click Go (or Search Again). Under Integrated Circuits (ICs) click on PMIC - Voltage Regulators - Linear (34,840 items) Check the box next to In Stock and under Regulator Topology click on Positive Adjustable, Click on Apply filters. Scroll to the right, under Number of Regulators select 1, under Mounting Type select Surface Mount, and under Supplier Device Package select SOT223-3. Scroll back to the left and click on Apply filters.

PlainBill

[dossman]

Re: Vizio VW42lHDTV10A no pix, no sound, won't turn off

From the manual for the VL42HDTV10A the U9 is listed as the same chip as the U7 but on my board they have different numbers. someone mentioned that this U9 is fixed and not adjustable so I looked up the U7 on Digikey and filtered the search for fixed instead of adjustable and here is what I got.

http://search.digikey.com/scripts/Dk...117E18GDICT-ND

[dossman]

Re: Vizio VW42lHDTV10A no pix, no sound, won't turn off

Thanks Plainbill, without your knowledge and experience there would certainly be no hope for most of us here. I do know about the manufacturer difference on the first letters of the part. I got confused reading the manual becuase it was for a slightly different TV model (and there are changes). Could that be the reason why some of the same parts have different prices on them as well?
The ZLDO1117GDICT input voltage is 2.7 - 18 volts while the AP1117EGDICT-ND is 6.4 - 18 volts. The manual I have did not even say to check the U9 in the troubleshooting flowchart so that's why I overlooked it. There is also a U10 regulator located to the far left side of the board but its pin #2 is not even connected at all. I got 2.66 volts on pin #2 which is good but why is the pin not connected? This U10 looks like a TO-252 case design and is located in the photo just right of the large white silkscreened numbers. Sorry about the flash. Thanks again

[dossman]

Re: Vizio VW42lHDTV10A no pix, no sound, won't turn off

Kingofcoins did you get your set up and running yet?

[PlainBill]

Re: Vizio VW42lHDTV10A no pix, no sound, won't turn off

Thanks Plainbill, without your knowledge and experience there would certainly be no hope for most of us here. I do know about the manufacturer difference on the first letters of the part. I got confused reading the manual becuase it was for a slightly different TV model (and there are changes). Could that be the reason why some of the same parts have different prices on them as well?
The ZLDO1117GDICT input voltage is 2.7 - 18 volts while the AP1117EGDICT-ND is 6.4 - 18 volts. The manual I have did not even say to check the U9 in the troubleshooting flowchart so that's why I overlooked it. There is also a U10 regulator located to the far left side of the board but its pin #2 is not even connected at all. I got 2.66 volts on pin #2 which is good but why is the pin not connected? This U10 looks like a TO-252 case design and is located in the photo just right of the large white silkscreened numbers. Sorry about the flash. Thanks again

When you see a device that has three pins and a tab, the tab is often (usually?) electrically connected to the middle pin. That's the case on this regulator, and on all the xx1117- family of regulators.

PlainBill

[dossman]

Re: Vizio VW42lHDTV10A no pix, no sound, won't turn off

I'm stuck on one chip Bill, it is U10. I took a much better photo of it so you can read the numbers. I looked on Digikey but there are many different voltages. I'm assuming the 07 stands for the output voltage but 0707GL does not make sense to have 7 volts out and in to me. Please take a look as I am on hold here with the order. http://search.digikey.com/scripts/Dk....dll?Selection