Vizio V032L FHDTV10A Comes On Intermittently?

[rebelkustoms]

For your consideration I just picked up a free 32 in Vizio VO 32L. Woman said it no worky, but I plugged it in and I always get an orange light and can hit the power and turn it white. First time I did this it stayed white with no pic etc. But the set "freezes" like this and cannot be turned off unless unplugged. So I left it lile that while I did some research and after 20 min. The picture appeared. I thought it a cold solder joint or a fritzy cap so I began by reflowing most joints on the pcb. (No luck) then I took to a full recap of the pcb on the advice of the friendly dude who runs the electronics store in STL. (No fix either). Poked around on it some more this evening after it was off a few days and decided to light it up to check pinouts again. It turned on screen and all when plugged in and I can cycle through menu etc. So I cycled power off to see what would happen and it did the old white logo, no screen , Freeze up. My pinout voltages seem good, only thing to note is my 12v pins are reading 11.8 - 11.9. But everything else looks intact. Any advice would help. I love the look of this thing and would like to fix it. Could I be dealing with a main board issue here? Pics Attached please let me know if something isnt clear or more photos are needed. Thanks.

[budm]

Re: Vizio V032L FHDTV10A Comes On Intermittently?

"But the set "freezes" like this and cannot be turned off unless unplugged." That is the sign of bad main board, there are many 3-pin Voltage regulator IC's that you need to test the Voltages on all three pins with ref. to chassis GND., report what they are for each one. Bad regulator IC's in Vizio are common problem.

[rebelkustoms]

Re: Vizio V032L FHDTV10A Comes On Intermittently?

Cool I will look at them tomorrow and use the Voltage reg test link below your post.

[rebelkustoms]

Re: Vizio V032L FHDTV10A Comes On Intermittently?

OK Finally got a minute alone to test voltages on Voltage regulator pins on main board. I have only tested these things once or twice so i am trying to educated guess Voltin, Voltout, and GND so if readings look weird I may have a reading swapped but you may be able to guess by 12v in- 5v out etc. I have gained a vast amount of experience in the LAST YEAR BUT i AM STILL LEARNING SO HERE GOES.

(Refer to pic of Main Board in earlier post)


IN GND OUT
U16 11.7v 1.1mv 5v

U15 5v 2v 3.3v

U20 3.2v .5v 1.8v

U26 5v 1mv 1.25v

U44 8v 9.5v 11.7v

U22 3.3v 2.0v 5v

U19 5v 1.2v 2.5v

U21 2.5v 1.1mv 1.2v

U17 5.0v 2.0v 3.3v

[nomoresonys]

Re: Vizio V032L FHDTV10A Comes On Intermittently?

I would grab a main board, think I saw one on ebay for 35 bux or so. May find one here or somewhere else. Could confirm or eliminate the main board if you get a good one that is. If it turns out not to be the main board, it's always nice to have a spare.

[budm]

Re: Vizio V032L FHDTV10A Comes On Intermittently?

OK Finally got a minute alone to test voltages on Voltage regulator pins on main board. I have only tested these things once or twice so i am trying to educated guess Voltin, Voltout, and GND so if readings look weird I may have a reading swapped but you may be able to guess by 12v in- 5v out etc. I have gained a vast amount of experience in the LAST YEAR BUT i AM STILL LEARNING SO HERE GOES.

(Refer to pic of Main Board in earlier post)


IN GND OUT
U16 11.7v 1.1mv 5v

U15 5v 2v 3.3v

U20 3.2v .5v 1.8v

U26 5v 1mv 1.25v

U44 8v 9.5v 11.7v

U22 3.3v 2.0v 5v

U19 5v 1.2v 2.5v

U21 2.5v 1.1mv 1.2v

U17 5.0v 2.0v 3.3v

The small LDO regulator (1117 series) pinout is not the same as the large TO-220 case.
The 1117 can be Adjustable out put type or Fixed output type.
The fixed output will have something like '1117-33' printed on the body it indicates that it is 3.3V fixed output regulator. The adjustable will have '1117' printed on it.
Read this thread on how to find out if the Voltage readings are OK or not.
https://www.badcaps.net/forum/showth...999#post300999

[rebelkustoms]

Re: Vizio V032L FHDTV10A Comes On Intermittently?

OK So I went over the Voltage Reg Tests Again. Intermittently I can get this thing to turn on so I kept trying hoping to get that to happen and compare voltages from when it turns on and when it "Freezes". I could not replicate that so I took readings of the Frozen state again having watched the video and noting which pins were voltage in/ out / and ground. Here they are Most things here seem good because the Video [posted says that the Ground is Usually 1.25V lower than the Voltage Out pins.

U44 GND > 8.3 VO> 9.5 VI>11.7
U22 GND> 2.0 VO>3.3 VI> 5.0
U17 GND>2.0 VO>3.3 VI>5.0
U19 GND>1.2 VO>2.5 VI>5.0
U21 GND>0 VO>1.25 VI>2.5

Can anyone give me any insight into if any of these may be SUSPECT or BAD? thANKS

[budm]

Re: Vizio V032L FHDTV10A Comes On Intermittently?

They look OK.
BTW, U44, 22, 17, 19 you call GND pins are actually ADJ pin.
The good adjustable regulator will always have 1.25V between the ADJ pin and the Output pin.
So if the ADJ adj pin shows 1.2V and then you add 1.25V (INTERNAL Vref. is 1.25V) so the output should be = to Adj1.2V + Vref1.25V = 2.45V which is within +/-3% output tolerance.

[rebelkustoms]

Re: Vizio V032L FHDTV10A Comes On Intermittently?

Well, I am glad I finally figured out how to test these correctly, that will definitely com in handy. BUT if they are all good then I am am kind of out of Ideas here. Anything else I can check to see why this thing turn on with no backlight and gets stuck?

[rebelkustoms]

Re: Vizio V032L FHDTV10A Comes On Intermittently?

Bump still trying to sort through this one any help would be appreciated.

[dskall]

Re: Vizio V032L FHDTV10A Comes On Intermittently?

There is an eeprom for this board. You might try freezing eeprom and see if that improves things. Ic with blue dot

[rebelkustoms]

Re: Vizio V032L FHDTV10A Comes On Intermittently?

well I got a chance to go over this guy last night and to no avail. I tried freezing the Eprom and several other components and powering on and I got the same out come. Any Ideas Anyone. Thanks in advance.