Samsung le37b530 flickering backlight

[apeter1]

Re: Samsung le37b530 flickering backlight

Is only the 55.37T05.C09 good for my tv or all T370HW02 37T04-C0G board with similar numbers?

[apeter1]

Re: Samsung le37b530 flickering backlight

Hi,

The store has only EC5575-HF so I could replace the AS15-HF on tcon to EC5575-HF. The bright colours flickering is disappeared but the colours are pale. Could it caused by the different chip type?

Thanks,
Péter

[apeter1]

Re: Samsung le37b530 flickering backlight

Hi,

Could be damaged the chip during soldering?

Thanks,
Péter

[apeter1]

Re: Samsung le37b530 flickering backlight

The black and blond is grey:

https://www.youtube.com/watch?v=9cAtkch5kr0
https://www.youtube.com/watch?v=9LpeqmUn1j8

[orinoco8]

Re: Samsung le37b530 flickering backlight

T-CON should be good (if image remains good through the flickering of backlight). Try to check the DIM and INV signals coming from mainboard to power supply.

[apeter1]

Re: Samsung le37b530 flickering backlight

There was not flickering of backlight. The title of topic is my fault. There was problem with bright colours: https://www.badcaps.net/forum/showthread.php?t=50132
What should I check between mainboard and power supply? How can I check it?

Thanks,
Péter

[orinoco8]

Re: Samsung le37b530 flickering backlight

No sure (I am not experienced enough with bright color flickering issues). You can still check the voltage of INV and DIM signals (from main board). See whether they change as the flickering intensifies.

[Cyberknight13]

Re: Samsung le37b530 flickering backlight

I am posting this here as I believe the issue on my TV is also a backlight problem. I am going to follow the steps in this thread, as well as similar ones here, but I wanted to post my specific problem in any case.

I have a Samsung LE37B530, specifically LE37B530P7WXRU (Russian model). The issue I am having is that when I power on the TV I usually get a black screen with sound. If I shine a flashlight on the screen I can see very faint images. Sometimes the TV will work normally and occasionally I get screen flicker intermittently.

The issue seems to have worsened over time as it started with just flickering when I was using the TV with my laptop via HDMI. Now it is almost always black screen with sound. I reset the TV to default settings via remote (exit button for 12 seconds then chose reset when it appeared on TV) but it did not seem to have any effect.

I am going to disassemble the TV now for troubleshooting and will advise.

[Cyberknight13]

Re: Samsung le37b530 flickering backlight

First video is with main board and power board connected and TV powered on. I get flickering, solid and rapid flickering backlights.

https://youtu.be/BLDHSPNx36g

Second video is with boards disconnected and TV powered on. I get solid lights on.

https://youtu.be/04RwkljgY5I

Third video is with boards disconnected and TV powered on. I get flickering lights.

https://youtu.be/uptMy9HI_HA

[Cyberknight13]

Re: Samsung le37b530 flickering backlight

Any advice based on the videos above? I'm a noob and not sure where to go next.

[budm]

Re: Samsung le37b530 flickering backlight

I would check the DCV between the two legs of the main filter cap to see what you have, it should be around 380~400VDC.

[Cyberknight13]

Re: Samsung le37b530 flickering backlight

I would check the DCV between the two legs of the main filter cap to see what you have, it should be around 380~400VDC.

Sir, thank you for the response and advice. I assume you mean the 2 big blue capacitors in the attached photos. I set the multimeter to 1000 DCV and get a 1 reading on both capacitors.

[budm]

Re: Samsung le37b530 flickering backlight

Sir, thank you for the response and advice. I assume you mean the 2 big blue capacitors in the attached photos. I set the multimeter to 1000 DCV and get a 1 reading on both capacitors.

1VDC? Are you sure your meter is OK? Where EXACTLY did you put the meter probes? TV plugged in and turned on?

[Cyberknight13]

Re: Samsung le37b530 flickering backlight

1VDC? Are you sure your meter is OK? Where EXACTLY did you put the meter probes? TV plugged in and turned on?

The multimeter works as far as I can tell. I tested it on some batteries and other components. I placed the probes on the exposed legs of the capacitors with the TV turned on and set the multimeter to 1000 DCV as the next closest option is 200 DCV. I did a quick video of it so you can see what I did. I hope I did everything correct and don't appear too foolish.

https://youtu.be/L6VbS2XmulI

[budm]

Re: Samsung le37b530 flickering backlight

The meter is telling you it thinks it is OVER RANGE even on 1000 VDC scale which is impossible. The meter is bad.

[Cyberknight13]

Re: Samsung le37b530 flickering backlight

The meter is telling you it thinks it is OVER RANGE even on 1000 VDC scale which is impossible. The meter is bad.

Roger that. I'll go get a new one on the 1st.

I'm assuming the capacitors are likely the problem with the TV due to the intermittent problem. I had a similar issue on a PC LCD once and replaced the capacitors. It still works fine 6 years later. The capacitors also aren't bulging but they aren't as recessed as I think they should be. I'll attach a pic but it is likely hard to tell. Obviously I'll do more proper troubleshooting once I replace my meter.

Thank you for you assistance and advice!

[budm]

Re: Samsung le37b530 flickering backlight

I am not suspecting the main filter caps problem but the PFC Boosted Voltage problem that is on the edge of shutting down/restart.

[Cyberknight13]

Re: Samsung le37b530 flickering backlight

I am not suspecting the main filter caps problem but the PFC Boosted Voltage problem that is on the edge of shutting down/restart.

Any idea where that would be and what it would look like on this TV? I understand the concept of what it is but otherwise lost on that one. Here is the service manual for this series of TV.

https://drive.google.com/open?id=0B4...FROQ19IeXV1cm8

[budm]

Re: Samsung le37b530 flickering backlight

Any idea where that would be and what it would look like on this TV? I understand the concept of what it is but otherwise lost on that one. Here is the service manual for this series of TV.

https://drive.google.com/open?id=0B4...FROQ19IeXV1cm8

That is why I have you measured the Voltage at the two legs of the main filter caps, but you need to get your meter to read the dcv correctly first.

[Cyberknight13]

Re: Samsung le37b530 flickering backlight

That is why I have you measured the Voltage at the two legs of the main filter caps, but you need to get your meter to read the dcv correctly first.

Understood, thank you sir. I'll likely get it on the 1st and pick your brain some more then.