Toshiba 49U5863DB Vestel 17MB130S, blank screen, no image, sound ok.

[nos_feratu]

Hi everybody,

As per title says, I have an Toshiba D-LED TV set 49U5863DB made on Vestel backbone: 17MB130S motherboard, 17IPS72 power supply and VES490QNDS-2D-U12 chassis which has backlight but no image is displayed. Even so if is hooked up to a input source, sound coming up okay, picture still missing regardless the input source. There is a bit of remote interaction as you can turn on and off but that's pretty much it, there is no control on volume. What I've done so far: because there is no blinking and the TV is booting up fine, I assumed the power supply and mainboard are okay and start straight by checking LVDS cable integrity (okay btw), input voltage on display board (I'm not sure what's the right name for it, it's the board at the end of the LVDS cable) and has 12.2V measured against the TV chassis. Next I looked after Vone which measured against chassis returned 0V. So, I start looking after bad capacitors and found the SMD in the picture having a shortcut.
My question is: is that a capacitor, cause by the look of it is look like one but is quite fatter than the rest? If so, how I can figure out the actual value cause I cannot read anything on it?
if it turn up the bit is not a capacitor and is just a fuse or a resistor what can I do next in terms of investigating the issue?

Any idea will be much apreciated.

[Diah]

Re: Toshiba 49U5863DB Vestel 17MB130S, blank screen, no image, sound ok.

if it was cap filter and shorted as you stated then you have F on the boards open.. could you show us the area where the LVDS connected to this panel boards

[nos_feratu]

Re: Toshiba 49U5863DB Vestel 17MB130S, blank screen, no image, sound ok.

Thank you for your quick reply. Fuse has been checked and is alright. Picture attached below.

[Diah]

Re: Toshiba 49U5863DB Vestel 17MB130S, blank screen, no image, sound ok.

then i don't think its shorted cap. can you lift one legs of it with out damage the print joint ?

[nos_feratu]

Re: Toshiba 49U5863DB Vestel 17MB130S, blank screen, no image, sound ok.

I'll try this tomorrow as I have the hot air gun to a friend who forgot to return it.
If is not a shorted cap, can you point another direction for investigation?

thank you million for your help.

[Diah]

Re: Toshiba 49U5863DB Vestel 17MB130S, blank screen, no image, sound ok.

if its not then focus on the main boards in case VCC3.3 V could find on the panel and no visual damage to the edge glass break of the film which deliver the VCC

[budm]

Re: Toshiba 49U5863DB Vestel 17MB130S, blank screen, no image, sound ok.

Hi everybody,

As per title says, I have an Toshiba D-LED TV set 49U5863DB made on Vestel backbone: 17MB130S motherboard, 17IPS72 power supply and VES490QNDS-2D-U12 chassis which has backlight but no image is displayed. Even so if is hooked up to a input source, sound coming up okay, picture still missing regardless the input source. There is a bit of remote interaction as you can turn on and off but that's pretty much it, there is no control on volume. What I've done so far: because there is no blinking and the TV is booting up fine, I assumed the power supply and mainboard are okay and start straight by checking LVDS cable integrity (okay btw), input voltage on display board (I'm not sure what's the right name for it, it's the board at the end of the LVDS cable) and has 12.2V measured against the TV chassis. Next I looked after Vone which measured against chassis returned 0V. So, I start looking after bad capacitors and found the SMD in the picture having a shortcut.
My question is: is that a capacitor, cause by the look of it is look like one but is quite fatter than the rest? If so, how I can figure out the actual value cause I cannot read anything on it?
if it turn up the bit is not a capacitor and is just a fuse or a resistor what can I do next in terms of investigating the issue?

Any idea will be much apreciated.

You have 3 small caps connected in parallel with that large cap you marked, so it can possibly be one or more of those 4 caps are bad, you just have to remove it one at time to see what will happen to the resistance reading when one cap is removed one at a time.

[nos_feratu]

Re: Toshiba 49U5863DB Vestel 17MB130S, blank screen, no image, sound ok.

today I'll do that, cause I have to reclaim my soldering hot air gun from on of my mates. I'll post updates as soon as I have some. Thank you very much for all the responses.

[nos_feratu]

Re: Toshiba 49U5863DB Vestel 17MB130S, blank screen, no image, sound ok.

Okay, replaced the cap with new one, still no joy. Problem is no capacitors does have any inscriptions on them so I just replaced it with a 10uF/50V non polarised cap.

Vone = 0

Any ideas considered.

[yokoono]

Re: Toshiba 49U5863DB Vestel 17MB130S, blank screen, no image, sound ok.

Vone = 0
1. Short circuit on VONE
2. Defect RT6939
3. Short circuit between circuits on the ribbons leading to the panel
4. Short circuit in panel.

[Diah]

Re: Toshiba 49U5863DB Vestel 17MB130S, blank screen, no image, sound ok.

Okay, replaced the cap with new one, still no joy. Problem is no capacitors does have any inscriptions on them so I just replaced it with a 10uF/50V non polarised cap.

Vone = 0

Any ideas considered.

what you are doing now will make you lost. also put every things back as its original.


my suggestion at POST#6, if you inspect the panel from front side and there no damage to edge glass of the thin film.. then mother boards problem and exact thee main IC as its play video signal processing and send the signal direct to the panel via 1 LVDS.
playing sound and switching input. doesn't mean this IC 100% Okay.. its sound to me it had BGA Issue... reflow it after you take out the heat sink.

[nos_feratu]

Re: Toshiba 49U5863DB Vestel 17MB130S, blank screen, no image, sound ok.

@yokoono thank you for you idea I'll check for damages and shortcuts.

@Diah thank you for your advice, very much appreciated.

I'll come back with updates.

[budm]

Re: Toshiba 49U5863DB Vestel 17MB130S, blank screen, no image, sound ok.

Okay, replaced the cap with new one, still no joy. Problem is no capacitors does have any inscriptions on them so I just replaced it with a 10uF/50V non polarised cap.

Vone = 0

Any ideas considered.

But did you check the resistance of the empty pads to see if the short/low resistance still present or not after the cap is removed? As I also indicate, you have 4 caps connected in parallel.

[nos_feratu]

Re: Toshiba 49U5863DB Vestel 17MB130S, blank screen, no image, sound ok.

@budm thank you for your reply, yes I did tested, shortcut gone.

tomorrow I'll move my "workshop" from living room to garage for more space and peace of mind. I'll investigate more about possible causes.

I'll keep all updated.

[budm]

Re: Toshiba 49U5863DB Vestel 17MB130S, blank screen, no image, sound ok.

So the removed cap tested as short then? And with new cap installed the shorts is gone, correct?

[nos_feratu]

Re: Toshiba 49U5863DB Vestel 17MB130S, blank screen, no image, sound ok.

yes correct, removing the bad cap shortcut was gone, installed a new one but not having a clue about the value, just put a generic 10uF/50V nonpolarised.

[jimbofz]

Re: Toshiba 49U5863DB Vestel 17MB130S, blank screen, no image, sound ok.

one thing for you to check if you remove the bezel ,
lie tv on its back screen facing up and rebove all the small screws
once the bezel of surround has been removed look very close at panel edge where foils are attached .to see if any corrosion due to spillage .sometimes attempts to clean the screen allow fluid to drop down and contaminate the board ,use a magnify glass to examine this area and also all around the edge of the panel for any sign of damage checking this could save you a lot of grief

[budm]

Re: Toshiba 49U5863DB Vestel 17MB130S, blank screen, no image, sound ok.

https://www.badcaps.net/forum/attach...2&d=1604772421

Can I see the picture without that yellow circle?

[nos_feratu]

Re: Toshiba 49U5863DB Vestel 17MB130S, blank screen, no image, sound ok.

one thing for you to check if you remove the bezel ,
lie tv on its back screen facing up and rebove all the small screws
once the bezel of surround has been removed look very close at panel edge where foils are attached .to see if any corrosion due to spillage .sometimes attempts to clean the screen allow fluid to drop down and contaminate the board ,use a magnify glass to examine this area and also all around the edge of the panel for any sign of damage checking this could save you a lot of grief

thank you for the idea, I'll do that as soon as I get a more suitable space to work, other than living room floor

[nos_feratu]

Re: Toshiba 49U5863DB Vestel 17MB130S, blank screen, no image, sound ok.

https://www.badcaps.net/forum/attach...2&d=1604772421

Can I see the picture without that yellow circle?

yes of course, picture attached. thanks to @jimbofz I found the circled smd is an actual fuse, not a capacitor, suppose to have 0 resistance