Sony KDL32L5000 screen stays black but audio works fine

[Mandraco]

Hello friends, I'm having trouble with a Sony LCD tv, at first it showed some vertical lines but they were incomplete lines. Some started at the top solid green in color and started fading the nearer they got to the center of the screen others faded near the fourth quarter of the screen. Others looked faded in the center of the screen and hot more solid as they approached the bottom while some others crossed the screen from top to bottom. There was about four consecutive horizontal lines at the top of the screen and near the bottom half.

Well, I put it aside until recently when I took a look inside the t.v. I couldn't see any bulged or leaking caps so I tried to check the small board connected to the LCD panel.
1- I removed the flex cable going from the board( I think it is called T control) and saw no image so...

2- I connected the flex back,this time TV was still ON. The screen turned white entirely.

3- I turned TV off and reseated the cable, turned it ON and now the screen was black.

4- I hooked up my DVD via Red,Yellow,White cables and managed to get to the input until I heard sound. Now that's the current state of my TV.

I notice the relay clicks 1-2 seconds after I plug it to the electric outlet and clicks again approx. 2 seconds after the first click. I removed the cord from the electric outlet and removed the connector going from POWER board to AV board and plugged the TV back to the outlet, there was no click at all. Also there is a series of very rapid clicks when I disconnect the TV from electricity after it has been on for a while, they sound like TRRRR.

I tested the 14- pin connector going from POWER board to AV board, connector CN6201 the readings are with TV ON / TV OFF for each of the colors from top to bottom. Readings from the connector are as follows:

At the top there is a pin labeled "REG 12V" This one is unused, the others correspond to a cable which color I mention along with the reading for it.
THE UNUSED PIN ALSO READS 0 / 11.89

The next are marked REG 12V
BLACK= 0 / 11.89
BROWN= -0, 0 / 11.89
RED= 0 / 11.89
The next are marked REG12V GND
ORANGE= 0 / -0
YELLOW= -0,0 / -0
GREEN= 0 / -0
The next are marked UREG 15V AU-GND
BLUE= 0 / -0t
PURPLE= 0 / -0
GRAY= 0 / 16.56
WHITE= 0 / 16.56
The next is marked SYBY 3.3V
BLACK= 3.26-3.31 / 3.31
The next is marked AC DET
BROWN= 2.81 / 2.79
The next is marked P ON
RED= 0.02 / 2.72

Any help would great, I reposted this here since by an error I originally posted to the "Announcements and Related News" section, sorry for any confusion that may cause and thanks in advance.

[stj]

Re: Sony KDL32L5000 screen stays black but audio works fine

can you post a foto of the power supply.

[Mandraco]

Re: Sony KDL32L5000 screen stays black but audio works fine

Thanks for the reply, yes, I can but I'm using a cell phone, is there a limit for size, resolution of pictures?

[stj]

Re: Sony KDL32L5000 screen stays black but audio works fine

no, bigger is better - but upload them.
dont link to a foto host.

[Mandraco]

Re: Sony KDL32L5000 screen stays black but audio works fine

Hello, I'm having trouble attaching the pictures from my windows phone, it seems I need to find a working PC since mine is dead for a couple of months now. I'll try to get to a PC and then upload them. Or maybe I can try to upload them to my file sharing account and use the "upload from URL" option. What should I do, friend?

[stj]

Re: Sony KDL32L5000 screen stays black but audio works fine

upload from url should work.

[Mandraco]

Re: Sony KDL32L5000 screen stays black but audio works fine

Hello stj, I thought I could use mediafire to upload you my pictures but the service's loader doesn't work either. I was able to upload pictures to SkyDrive, though I can't get the link to the folder in order to share it here. Any other ideas as to how can I upload the pictures? I'm using a Lumia 920, since my laptop is having problems with startup... This is so frustrating :-/

[Mandraco]

Re: Sony KDL32L5000 screen stays black but audio works fine

Hello, stj, at least I got my hands on a PC I attached three pictures: The first one is a full view of the back of the TV without the back cover, the second is a closeup of the POWER board and the other is a closeup of the connector where I tested all those PINs (CN6201 ), I hope that helps you a bit, thanks for the patience.

[stj]

Re: Sony KDL32L5000 screen stays black but audio works fine

1st thing that comes to mind,
where the fuck did all that rust come from??????

[Mandraco]

Re: Sony KDL32L5000 screen stays black but audio works fine

Well I live in a tropical place, the weather changes unexpectedly every day and maybe that has some effect on that guard. Every price of electronics I've checked is the same after a couple of years of normal use. I have noticed some devices accumulate dust and that dust creates an area of oxidation on the metal plates covers in many of them, mostly video games consoles.

Does the rust matters? I've seen TVs that look worse than this which are completely functional, though.

[budm]

Re: Sony KDL32L5000 screen stays black but audio works fine

So right now, do you still have 12VDC on both ends of the SMD F1 on the T-CON board? I have a feeling you have bad panel.

[stj]

Re: Sony KDL32L5000 screen stays black but audio works fine

rust matters on chip or transistor pins because they are close enough for it to touch.
and lead-free solder can rust - i'v seen it!

[Mandraco]

Re: Sony KDL32L5000 screen stays black but audio works fine

I have read other threads here and some asked to test some "dots" found on the TCON board, I don't remember all the names for each one of those little dots(VCC, VSS, VON and such) but most of them bring no reading on my multimeter. About the SMD FUSE you might be referring to one marked FP1,looks made out of ceramic, at its right is one of those dots labeled VIN, below the FP1, CON1 is located(the cable coming from the board which has all the video and audio inputs.

I'm not home now, I'll check the fuse when I arrive and report back to you, thanks.

[Mandraco]

Re: Sony KDL32L5000 screen stays black but audio works fine

I know about the corrosion you talk about, but what I've seen is more like green or blueish in color than the brown/red of this one. I checked the pins and they are OK, no rust or corrosion detected. I live in Puerto Rico so maybe the corrosion in the metal Shields are expected. Most if the equipment is like that, over here you can have a hot day with temperature around 95 degrees and suddenly it starts to rain and you cam see the steam raising from the ground. The greater portion of population lives in rural homes like myself, that means no air conditioner which means old fashioned ventilation with windows open 24/7 and a lot of dust comes into the house. I also live 7 miles from the coast... Too many factors to consider but it affects mainly exposed metal, but if you look closer the picture you will see the RCA connectors metal on the outside is like new, no rust. That makes me think it has more to do with the high temps under that shield, as it happens with cars exhausts/ mufflers.

[bammbammfran]

Re: Sony KDL32L5000 screen stays black but audio works fine

Since you use to have a picture with some lines and now no picture, I would opt to try a new t-con board if you can find one at a decent cost

[Mandraco]

Re: Sony KDL32L5000 screen stays black but audio works fine

Hello, I used my multimeter at 20 VDC and placed the BLACK probe on the chasis/ metal to which the boards are adjusted and the RED probe to each side of the FP1 FUSE with the TV turned on(I could see the backlight): on one side I get 11.86 while on the other I only get 0.18.

I have read some threads and see they ask about the readings on some spots or dots that look like open trails. I think they are there so you can pinpoint the component giving you trouble or at least to know how much Voltage you get to specific areas or components like ICs, connectors and so on. I can check them and post the results later. What should I do now?

[stj]

Re: Sony KDL32L5000 screen stays black but audio works fine

fuse is bad.
maybe for fun, maybe because of something else.

[Mandraco]

Re: Sony KDL32L5000 screen stays black but audio works fine

maybe for fun, maybe because of something else.

I don't understand what you mean by this. What is for fun or because something else? Should i get a FUSE replacement?

[vinceroger69]

Re: Sony KDL32L5000 screen stays black but audio works fine

some fuses can blow for no apparent reason something else maybe a shorted capacitor etc etc i would just replace the fuse with the correct amps and voltage and try it.

[budm]

Re: Sony KDL32L5000 screen stays black but audio works fine

The fuse may have blown due to this:
"2- I connected the flex back,this time TV was still ON. The screen turned white entirely"