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Old 04-20-2015, 05:57 PM   #1
jayz28
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Default 3007wfp screen flicker after warmup

Hi everyone,

I'm hoping someone can shed a little light on what might be going wrong with my trusty old 3007wfp, which recently started to develop this strange flicker:
https://lh5.googleusercontent.com/-H...420_093357.mp4

It usually happens after 15 mins of the monitor being on, and will reliably go away if I shut it off for an equal amount of time. In searching the forums, I know that the D22 diode on the 3007 is a common problem, but it seems to cause different symptoms (no image) than what I'm seeing. Is my issue more likely to be a bad cap or possibly a faulty tcon?

Thanks,
Jay
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Old 04-20-2015, 06:09 PM   #2
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Default Re: 3007wfp screen flicker after warmup

Quote:
Originally Posted by jayz28 View Post
Hi everyone,

I'm hoping someone can shed a little light on what might be going wrong with my trusty old 3007wfp, which recently started to develop this strange flicker:
https://lh5.googleusercontent.com/-H...420_093357.mp4

It usually happens after 15 mins of the monitor being on, and will reliably go away if I shut it off for an equal amount of time. In searching the forums, I know that the D22 diode on the 3007 is a common problem, but it seems to cause different symptoms (no image) than what I'm seeing. Is my issue more likely to be a bad cap or possibly a faulty tcon?

Thanks,
Jay
Open her up and get some pics of the boards
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Old 04-21-2015, 11:10 AM   #3
jayz28
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Default Re: 3007wfp screen flicker after warmup

Took her apart this morning and here are the boards:

Power:
https://lh3.googleusercontent.com/-g...421_095533.jpg

IO:
https://lh5.googleusercontent.com/-y...421_095554.jpg

TCON:
https://lh5.googleusercontent.com/-M...421_100008.jpg

No obvious blown components on any of the 3 boards.
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Old 04-22-2015, 12:03 AM   #4
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Default Re: 3007wfp screen flicker after warmup

I desoldered the 3x 100uF 25v caps on the IO board, which appear to have been replaced with UCC KY series caps already. All 3 measure out well within spec to 0.11ohm ESR. I'll likely replace them anyway. Next up, caps on the power supply board.
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Old 04-22-2015, 10:17 AM   #5
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Default Re: Dell 3007wfp screen flicker after warmup

After inspecting the power supply board, it appears several caps (orange ones in the image) here have also been replaced with UCC caps. Should I bother replacing the rest of the LTec and Taicon caps or is the nature of the failure more indicative of a bad TCON?

Here's a better video of what the LCD is doing:
http://goo.gl/O1TKmI
Attached Images
File Type: jpg 20150421_095533.jpg (192.4 KB, 18 views)
File Type: jpg 20150421_095554.jpg (253.8 KB, 13 views)
File Type: jpg 20150421_100008.jpg (309.4 KB, 12 views)

Last edited by jayz28; 04-22-2015 at 11:41 AM.. Reason: Added pictures
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Old 04-22-2015, 11:08 AM   #6
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Default Re: 3007wfp screen flicker after warmup

I have looked at the video again and it is not flickering in normal sense.
By pausing it every few seconds it appears it is redrawing the picture not necessarily in the same place. I dont know but it suggests a tcon fault.
BUT may be due to a power surge from the power supply.
Have you tried a different monitor on the PC to cut out the graphics card.
Tried this monitor on a different PC. Tried changing the refresh rate.

We would prefer the still pictures to be posted using manage attachments so they remain for future enquirers.
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Please upload pictures using attachment function when ask for help on the repair
http://www.badcaps.net/forum/showthread.php?t=39740
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Old 04-22-2015, 12:00 PM   #7
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Default Re: 3007wfp screen flicker after warmup

Quote:
Originally Posted by selldoor View Post
I have looked at the video again and it is not flickering in normal sense.
By pausing it every few seconds it appears it is redrawing the picture not necessarily in the same place. I dont know but it suggests a tcon fault.
BUT may be due to a power surge from the power supply.
Have you tried a different monitor on the PC to cut out the graphics card.
Tried this monitor on a different PC. Tried changing the refresh rate.

We would prefer the still pictures to be posted using manage attachments so they remain for future enquirers.
Yes, I've tried this monitor on multiple PCs and my laptop, and they show the same issue. I've also tried different refresh rates and different resolutions to no avail. Are there any tests I can do to further indicate that it's a TCON failure before replacing the entire board?

Images Attached.

Thanks.
Attached Images
File Type: jpg 20150421_095533.jpg (192.4 KB, 4 views)
File Type: jpg 20150421_095554.jpg (253.8 KB, 6 views)
File Type: jpg 20150421_100008.jpg (309.4 KB, 10 views)

Last edited by jayz28; 04-22-2015 at 12:02 PM.. Reason: attach images
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Old 04-22-2015, 01:19 PM   #8
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Default Re: 3007wfp screen flicker after warmup

I dont know of any tests that would prove it others might.

On think to try is to measure the voltage either on the fuse or where there is a testpoint vin15 and see if it is constant.

As the problem appears after 15 minutes it may be heat related. Get a hair dryer and gently heat sections of the boards at a time and see if you can get it to go off ( flicker) quicker. If you get it to do that then let it cool and try pinpoint the area, then a component.
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Old 08-15-2016, 07:36 PM   #9
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Default Re: 3007wfp screen flicker after warmup

Folks,

One of my 3007wfp has developed exactly the same problem as shown in the animated gif posted above by the OP. It would work perfectly well from cold but after some time strange shadows would start to run across the screen from right to left as if somebody was painting it with a brush in horizontal strokes. Gradually the picture would fade into an almost white screen. I suspect that some component(s) in the T-con board are changing their characteristics due to heat. Did anyone ever find what was causing this?
Attached Images
File Type: jpg DSC01244.jpg (1,009.5 KB, 12 views)
File Type: jpg DSC01246.jpg (953.5 KB, 12 views)
File Type: jpg DSC01248.jpg (649.8 KB, 12 views)

Last edited by HAHOMETP; 08-15-2016 at 07:39 PM..
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Old 08-20-2016, 03:37 PM   #10
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Default Re: 3007wfp screen flicker after warmup

Update.

A replacement T-con board from ebay has cured the problem. The issue is closed.
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Old 08-20-2016, 08:16 PM   #11
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Default Re: 3007wfp screen flicker after warmup

Update 2.

After working fine for a few hours the monitor is now flashing random horizontal stripes again. The replacement T-con board did not help.
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Old 06-19-2017, 08:51 AM   #12
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Default Re: 3007wfp screen flicker after warmup

Happy to report that the saga is finally over. The method that I had used to fix a Vizio M60-C3 HDTV back in February has worked just as well on my Dell 3007wfp monitor yesterday. I opened up the screen, cut the 6 flex chips off its RHS edge and put the monitor back together. The problem is gone.

I have attached a few pix.
1. This is how the bad side flex IC chips manifest themselves.
2. My two 3007wfp monitors, the bad one and the good one, side by side.
3. The once bad 3007wfp after I cut the side flex IC chips off its LCD.
4. The close up look of the side flex IC chips after they have been cut off the LCD. No discoloration, no burnt spots.
Attached Images
File Type: jpg DSC02580.jpg (350.9 KB, 13 views)
File Type: jpg DSC02581.jpg (435.8 KB, 13 views)
File Type: jpg DSC02871.jpg (503.3 KB, 12 views)
File Type: jpg DSC02872.jpg (655.8 KB, 14 views)

Last edited by HAHOMETP; 06-19-2017 at 08:58 AM..
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Old 06-19-2017, 09:43 PM   #13
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Default Re: 3007wfp screen flicker after warmup

Are there any side effects after removing those ic chips?
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Old 06-19-2017, 09:59 PM   #14
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Default Re: 3007wfp screen flicker after warmup

Not that I know of. Have a look at this thread on the same subject .
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