Samsung LE32R88BD sound but no picture

[Ian151]

I'm wondering if anybody can help me identify the possible cause of a fault.
I have replaced the PSU board and tried another AV board but the problem remains. Sound and visible backlight on screen but no picture or menu etc.
All caps on replacement PSU look to be okay but it wasn't a brand new board but a replacement sold as working on eBay. Any advice very welcome.

[capkid]

Re: Samsung LE32R88BD sound but no picture

I don't know this model very well, but I'd verify the PSU output voltages and check the voltage at the t-con's fuse (both sides of the fuse) to start.

[Ian151]

Re: Samsung LE32R88BD sound but no picture

Thanks for this, I will check PSU output voltages. Is the t-con fuse the main input fuse to the PSU board? Thanks

[capkid]

Re: Samsung LE32R88BD sound but no picture

The t-con is the small board that's located at the top of the panel. It should have its own fuse(s).

[Ian151]

Re: Samsung LE32R88BD sound but no picture

Thanks, very helpful pic. I will check.

[Ian151]

Re: Samsung LE32R88BD sound but no picture

I do not seem to be able to locate anything resembling a fuse on the t-con board. I might be missing it so I have uploaded a photo of board. Any suggestions would be welcomed. Thanks

[capkid]

Re: Samsung LE32R88BD sound but no picture

I see one at location "F1". It's at the right edge of the connector for the cable coming from the main board. It has "UD" inscribed on it.

[Ian151]

Re: Samsung LE32R88BD sound but no picture

Yes, found it. Should this have voltage across it? If so, what voltage would I typically expect to find? And again, many thanks for your help.

[Ian151]

Re: Samsung LE32R88BD sound but no picture

Okay, I've just run some checks on fuse "UD". Measuring 5.1v to ground on one side of the fuse and 0v on the other-side. Also ran a continuity test on "UD" and it appears to be open-circuit. Is there any way I can safely temporarily bridge this fuse to check the board's function. Thanks

[capkid]

Re: Samsung LE32R88BD sound but no picture

I believe you should be seeing something like 12V across the fuse, but I don't know for sure. Either way, your fuse is faulty. You can temporarily jumper the ends of the fuse with a piece of wire to test it.

A fuse I replaced on a Philips TV's t-con also had "UD" stamped on it. I replaced it with this fuse that was a little higher voltage: http://www.digikey.com/product-detai...5TR-ND/1206513

Edit: Instead of trying to remove the bad fuse and risking damage to the board, I just put the new one on top of the old one and soldered the ends of the fuse to the pad and old fuse.

[Ian151]

Re: Samsung LE32R88BD sound but no picture

Many thanks, I will try this and report back. Cheers

[Ian151]

Re: Samsung LE32R88BD sound but no picture

I have now temporarily bridged the fuse and refitted the t-con board. TV will not now switch on but delivers a sequence of stand-by light flashes. One quick flash followed by three slower ones. Then no light for about 5 seconds and then the above sequence again.
Disconnecting the t-con board takes the TV back to how it was, switching on, sound and backlight but no screen picture. Is it too simple to suspect a faulty t-con board?

[Ian151]

Re: Samsung LE32R88BD sound but no picture

I can obtain a replacement t-con board for about £35. Has anybody out there with the same symptoms replaced the t-con board and successfully rectified the problem? I am trying to avoid replacing all the boards one-by-one until I hit on the problem.
Thanks

[capkid]

Re: Samsung LE32R88BD sound but no picture

Boy, I'm like you in that I wouldn't want to continue board swapping to try to resolve this issue. Someone else may have an idea, but the blink code doesn't seem to lead to anything conclusive. It's either a 4-blink code or a 1-3 blink code. It seems to me that you've possibly exposed a fault on the t-con by bridging the fuse. One thing you could try is disconnecting each of the ribbon cables from the t-con to the panel to see if you get half a picture on either side of the panel.

[Ian151]

Re: Samsung LE32R88BD sound but no picture

Thanks for that, I will try it. I can source a replacement board from a company in San Diego, California, but it's $58 + PP. I need to decide whether the set is worth spending any more time and money on. Anyway, thanks for your help, I will let you you know if I manage to cure the fault. Cheers.

[jerryio]

Re: Samsung LE32R88BD sound but no picture

Instead of making a new thread I'll ask this here please as its the same problem..
How can I differentiate between a T-Con problem and an inverter problem, as they seem to have near to same symptoms?
thanks

[aaronwt6]

Re: Samsung LE32R88BD sound but no picture

A T-con problem is going to result in either no picture or a distorted picture. An inverter problem is going to result in the backlights not coming on.

[budm]

Re: Samsung LE32R88BD sound but no picture

@IAN, you may want to check the resistance of those MLCC (Multi Layer Ceramic Capacitor) the brown rectangular shape to see if they are shorted. You should also disconnect those two white ribbon to the LCD panel to see if the TV will turn since the LCD panel may have shorted IC drivers for the X/Y TFT.

[capkid]

Re: Samsung LE32R88BD sound but no picture

Thanks for that, I will try it. I can source a replacement board from a company in San Diego, California, but it's $58 + PP. I need to decide whether the set is worth spending any more time and money on. Anyway, thanks for your help, I will let you you know if I manage to cure the fault. Cheers.

Yeah, I wouldn't spend $58+ on a replacement t-con for a 32" TV, especially after having spent as much as you have to this point. Try the ribbon test, and also take Bud's suggestion about checking the caps on the t-con.

The MLCC's are labeled CPxx on the t-con. How I would test them is by setting the meter to the ohms scale and simply placing your probes on either end of the cap. If you get a really low resistance on any cap (e.g. 0.5 ohms), you may have a short in the cap. I say maybe, because you might have a failed component near the cap.

[Ian151]

Re: Samsung LE32R88BD sound but no picture

Hi,
Update on the Samsung LE32R88BDX with no picture. Eventually decided to replace the T-con board but couldn't source one in the UK. Found a company on eBay in San Diego, California who had the correct version.
Part arrived today, fitted it and hey guess what? It works, brilliant!
Thanks to all who helped point me in the right direction and especially Capkid.