HELP Please with faulty TV

[Berts]

Hi,

I wonder if you can help I have a Toshiba 32V500B. After a while of being on 1 min or so, a red hue appears on the screen and gradually gets worse.

So far I have changed the inverter, power board and output boards.

What else could it be?

I will attach 2 pictures to show you before and after 1 minute of being on.

regards

Berts

https://www.dropbox.com/s/uxy2r5a67w...2000.54.12.jpg

https://www.dropbox.com/s/p5vswcwijourrty/IMAG0317.jpg

[tom66]

Re: HELP Please with faulty TV

There should be an additional letter before "V".

Looking at the menus I'd say you've got a Vestel built Toshiba (if that letter is a "B", "D", "S" or "K"), which is the same as a Bush or Alba or any other supermarket cheapie. (You would be right to be disappointed if this is the case.)

A lot of bad panels on these models, due to tab bonds. It is usually fixable though.

[Berts]

Re: HELP Please with faulty TV

Ah yes "K" my bad. Its not actually my TV but said I would fix it, thinking that if I replaced all the boards as I have done with others that would sort it. But no joy

How would I fix these "tab bonds" and where are they situated?

Thankyou for your time too, really appreciate it.

Bert

[tom66]

Re: HELP Please with faulty TV

The tab bonds are on the edges of the LCD panel itself. The operation is difficult but typically achieves over 90% success rate.

Different faults, but same base cause:
https://www.youtube.com/watch?v=xHst6pKLtTE
https://www.youtube.com/watch?v=purk_SyiT44

[Berts]

Re: HELP Please with faulty TV

Excellent thanks for your help Tom I will post back how I get on.

Respect

[Berts]

Re: HELP Please with faulty TV

Ok, so I tried looking at the tabs and no help.

I thought that if I uploaded a video for you that might help?

https://dl.dropbox.com/u/74442358/20...2023.23.37.mp4

I really am stuck with this one ???

[Berts]

Re: HELP Please with faulty TV

Does that link work ok for you guys?

[tom66]

Re: HELP Please with faulty TV

Downloading it now, slow internet.

[Berts]

Re: HELP Please with faulty TV

Yeah its a big file too HD

[Berts]

Re: HELP Please with faulty TV

Any Ideas Tom?

[tom66]

Re: HELP Please with faulty TV

Sorry, forgot entirely about this post.

Red hue slowly fading is T-con or panel, or perhaps the supply voltage to the T-con.

When the hue appears have you tried pressing the bonds? On the IC as well as the bond->LCD and board->bond areas?

Also, try slowly and carefully heating them with a hairdryer to see if you can get the effect to occur quicker.

[Berts]

Re: HELP Please with faulty TV

Thanks, I will have a play tonight and repost my findings, thanks again for your time.

[Berts]

Re: HELP Please with faulty TV

Tom, I tried the points you noted above and cannot get any reaction. I did however find that if I let the red hue start and then removed and reattached the T-Con ribbon cable the hue disappeared instantly?

I have included another video for your review if you wouldn't mind taking a look and sharing your thoughts?

https://dl.dropbox.com/u/74442358/VIDEO0029.mp4

Regards

[tom66]

Re: HELP Please with faulty TV

You may have a loose cable, temperature sensitive component or cold solder joint on the T-con. Regional heating or freezing using cold spray (compressed air works too) may help find where the problem is.

[Berts]

Re: HELP Please with faulty TV

Yes I have tried cold spray and could not find the cause. If it were a temperature sensitive component I would assume that unplugging the T-con and re attaching it so quickly would not have the effect I am getting. The hue takes just as long to come back after the quick unplug as it does if I start the panel from cold.

Do you think the re flowing the T-con panel would help. I have various equipment round here to do it. I could even use a hot air wand to resolder each component if you think it will help?

[tom66]

Re: HELP Please with faulty TV

I think that would quickly risk damage to the LCD panel. It's not removable from the panel. Other things to check would be the supply voltage to the T-con.

[Berts]

Re: HELP Please with faulty TV

Not sure I know exactly where to test for the voltage.

[tom66]

Re: HELP Please with faulty TV

There should be a fuse on it.
http://www.google.co.uk/imgres?imgur...9QEwBg&dur=571

Voltage is measured at both ends with red probe on each end, black on chassis.

[Berts]

Re: HELP Please with faulty TV

Tom, I am getting 11.95v across the fuse. I am guessing that is good?

[tom66]

Re: HELP Please with faulty TV

Sounds good; is it stable when the picture goes red?