Samsung UE32F5000 (UK model) with no display. Power supply is OK.

[darkdead]

Re: Samsung UE32F5000 (UK model) with no display. Power supply is OK.

I just fix one of these and was a led i have to use my mulimeter testing evry led one by one and the lcd split is pure pain do it slow and carfull take your time.
The foil around the leds can be removed rotating the holders and then you have full acces to leds.
For test the led use decent multimerter on diode test and see if it show a tiny light and since the led pcb use white ink you have to scrach it for probe one by one.

[ralphup]

Re: Samsung UE32F5000 (UK model) with no display. Power supply is OK.

I just fix one of these and was a led i have to use my mulimeter testing evry led one by one and the lcd split is pure pain do it slow and carfull take your time.
The foil around the leds can be removed rotating the holders and then you have full acces to leds.
For test the led use decent multimerter on diode test and see if it show a tiny light and since the led pcb use white ink you have to scrach it for probe one by one.

Just got one from my Brother, tested all LEDS on the Strips as you advised with my Multi Meter. two dead LEDS (no glow when applying Multimeter, on two separate strips so removed LEDS on the strip, still no backlight.

How can I prove if anything else is the cause, I was hoping to get the LED Matrix lighting up minus the 2 removed LEDS.

[budm]

Re: Samsung UE32F5000 (UK model) with no display. Power supply is OK.

It is common failure, just have to get new LED, or LED strips and then make sure to turn down the backlights level to extend the life of the LEDs.

[ralphup]

Re: Samsung UE32F5000 (UK model) with no display. Power supply is OK.

It is common failure, just have to get new LED, or LED strips and then make sure to turn down the backlights level to extend the life of the LEDs.

Thanks, is there anywhere to measure to make sure I have good power to feed LEDS's only strips I can find are £30 a strip, would be a real waste to spend 60 to find PSU is not good.

PS any good places to buy these strips would help!

[ReeceyBurger123]

Re: Samsung UE32F5000 (UK model) with no display. Power supply is OK.

Does this set have an inverter BUDM ? lol

[ralphup]

Re: Samsung UE32F5000 (UK model) with no display. Power supply is OK.

turn down the backlights
Do you mean via the On-Screen Menu once the unit is working again budm?

[budm]

Re: Samsung UE32F5000 (UK model) with no display. Power supply is OK.

turn down the backlights
Do you mean via the On-Screen Menu once the unit is working again budm?

Yes, in the user on screen menu there is Backlights level adjustment (do not get confused with Brightness adjustment), most people have the TV set to full level which will make the LEDs running hot.

https://www.badcaps.net/forum/showth...335#post612335

https://www.badcaps.net/forum/showthread.php?t=51251

Both TVs are still function.

[ReeceyBurger123]

Re: Samsung UE32F5000 (UK model) with no display. Power supply is OK.

When the Leds get hot the Dye on them breaks down and eventually cracks meaning the whisker in the led no longer makes contact so there is no light output and no current can pass though it anymore.

[budm]

Re: Samsung UE32F5000 (UK model) with no display. Power supply is OK.

Does this set have an inverter BUDM ? lol

He said "Just got one from my Brother, tested all LEDS on the Strips as you advised with my Multi Meter. two dead LEDS (no glow when applying Multimeter, on two separate strips so removed LEDS on the strip, still no backlight."

[ReeceyBurger123]

Re: Samsung UE32F5000 (UK model) with no display. Power supply is OK.

No it was a joke on what was previously said on first page lol

[budm]

Re: Samsung UE32F5000 (UK model) with no display. Power supply is OK.

OK, the OP MIM never came back.

[ralphup]

Re: Samsung UE32F5000 (UK model) with no display. Power supply is OK.

Hi budm, thanks for all your help.

I found the image linking out the dead LEDS on your other post: https://www.badcaps.net/forum/attach...5&d=1431830352

If I do this on the TWO dead leds my Panel should light up?

again reason I ask is have gone down all five strips with multi meter and get a VERY faint glow from all LEDS apart from two, but after removing them still no back light, So is the Samsung not giving Power to the LEDS because of the Open Circuit or an I missing something else.

Is there any way to prove the PSU (there is one PIN giving 200+ Volts DC to ground.

Your help is REALLY appreciated! any detailed help on testing hte LEDS properly.

Do I really need 5 x 1N4007 and could I not connect them across the LED Pads from the removed LED?

The way I tested was to get my multi-meter with fine wires on the probes and poking them Under the lens/defuser, I would then get a faint glow on the LED being tested. If I get a faint glow would that indicate the LED is good? again not seeing a Bright light when testing like in your image https://www.badcaps.net/forum/attach...5&d=1431830352

[ralphup]

Re: Samsung UE32F5000 (UK model) with no display. Power supply is OK.

So is the reason I get no LEDS on at all due to the fact I have removed the 2 x LEDS (one from the top strip and one from the bottom strip) as it is basically a giant loop with all the LEDS in Series so any break in the Loop will break the whole series circuit, and if I bridge the 2 x Missing LEDS I will re-make the loop?

[budm]

Re: Samsung UE32F5000 (UK model) with no display. Power supply is OK.

So is the reason I get no LEDS on at all due to the fact I have removed the 2 x LEDS (one from the top strip and one from the bottom strip) as it is basically a giant loop with all the LEDS in Series so any break in the Loop will break the whole series circuit, and if I bridge the 2 x Missing LEDS I will re-make the loop?

The one you have are connected in series like Christmas lights so one goes open circuit the whole string will not light up.
Do not just bridge the bad LEDs you need to put either new LEDs or Diodes (5 in series) to form equivalent VF of the White LEDs otherwise if the constant current source cannot lower the current down (depends on the range of the circuit designed) to the safe level then you will damage other LEDs.

[martyparish]

Re: Samsung UE32F5000 (UK model) with no display. Power supply is OK.

Yes they are wired in series so when one goes out they all do.

Is there a part number on the led? I'd try to hunt them down and replace

[ralphup]

Re: Samsung UE32F5000 (UK model) with no display. Power supply is OK.

Yes they are wired in series so when one goes out they all do.

Is there a part number on the led? I'd try to hunt them down and replace

Ill try to strip the unit down again and take some photos, but the LCD Panel is a Samsung LCD Panel: SK09BN9501109ALM10F3A2857 CY-HF320BGSV1H

LED Strips are Sharp_FHD D2GE-320SC1-R0 5 strips with 9 LEDS

[ralphup]

Re: Samsung UE32F5000 (UK model) with no display. Power supply is OK.

another question budm.

http://www.ebay.co.uk/itm/Samsung-UE...3D182004820322
the labels are PINK, I believe this is a sign of overheating as only 2 strips on my unit are PINK and the rest are white, do you think that this is deliberate that the labels are sensitive to heat?

EDIT: scrap that just found ebay listing with yellow labeling..

[ralphup]

Re: Samsung UE32F5000 (UK model) with no display. Power supply is OK.

Hello budm, I have bridged the damaged LEDS with DIODES still not getting anything from the Backlight.

On PSU the 16 PIN CNL Connector (feeding the LEDS) is Labeled:

IF2 15 16 IF1
NC 13 14 NC
1- 11 12 1+
2- 09 10 2+
NC 07 08 NC
3- 05 06 3+
4- 03 04 4+
NC 01 02 NC

with the Unit powered up Im not reading anything across PINS 11/12 or PINS 09/10 or 05/06 or 03/04
I am reading 220V DC from Pin 12 to Chassis

[budm]

Re: Samsung UE32F5000 (UK model) with no display. Power supply is OK.

You do have the Voltage to drive the LED string, please recheck each LED and the polarity of the Diode you put in place and at the correct terminals of the bad LEDs.

[ralphup]

Re: Samsung UE32F5000 (UK model) with no display. Power supply is OK.

You do have the Voltage to drive the LED string, please recheck each LED and the polarity of the Diode you put in place and at the correct terminals of the bad LEDs.

well I believe I have tried everything, I did eventually short the temp diodes out, hoping that I would at least see the rest of the LED array light up just with power on for a couple of seconds, still nothing budm.

I appreciate all your assistance, and it would be great to get this screen back working, just at a dead end with it now.

I havent really been doing any major electronics the last few years, just a few console repairs.
not at work now, so from the top of my head when I check the LEDS with my MultiMeter in DIODE Mode, the display reads 0.777 for each LED then with the probes reversed I get 1 and the LED I am testing gives a faint glow, would that sound about right to you?