DELL P2717H 27 inch white horizontal lines on screen

[reaper422]

Hello,
I have a problem with the Dell monitor whit LCD Panel MV270FHM-N20
that starts with a normal picture but after three or four seconds of work, it starts to draw horizontal lines progressing from the bottom to the top.
The power supply generates stable voltages.
The power supply of the matrix is 5 volts, which is also stable.
I don't think normal sounds can be heard from the LVDS board.
After measurements are made on the test points on LVDS, the measurements are
VGH 23.7v
AVDDS 11.7v
AVDD 11.7v
VOFF -7.7v
VGL 7.4v
Vcom 4.7v
And in my opinion a DC-DC converter with a very high operating temperature.
Markings on it are, ER = 4C 334
Оn the board is marked as - IC201
Has anyone encountered anything like this, or does someone know the model of the IC?
Thanks in advance.

[lotas]

Re: DELL P2717H 27 inch white horizontal lines on screen

Er = 4c - er =xx - rt6801gqw (rt6801).

[reaper422]

Re: DELL P2717H 27 inch white horizontal lines on screen

Thanks.
I will order from aliexpress, and I will write if the repair has been successful.
If it is convenient to ask, where can I find a description for this type of marking?

[stefan222]

Re: DELL P2717H 27 inch white horizontal lines on screen

Hello,
I have similar Dell with the intermittent horizontal lines and the exact same IC is hot and produces weak hissing sound.
Interested to know if the repair worked.

[stefan222]

Re: DELL P2717H 27 inch white horizontal lines on screen

Just wanted to let you know that there is a cheap and dirty repair for this problem.
https://www.youtube.com/watch?v=O21ftJbbmr0

I did it because I got the monitor for free and didn't wanted to put too much effort into the repair. Mine is P2317H and I removed the exact same resistors and surprisingly it works!

Also, in comments there are people that talk about getting the lines back in a few months time. So it would be wiser to change the DC-DC chip.

[reaper422]

Re: DELL P2717H 27 inch white horizontal lines on screen

Thank you for the information.
The chips have arrived.
After replacing the DC / DC converter, the foreign sound disappeared but unfortunately, the converter heats up again and after a few seconds more the lines return.

[reaper422]

Re: DELL P2717H 27 inch white horizontal lines on screen

After a little more play I got to IC 102 after removing the resistors for VDD1 and VDD2.
The vertical lines disappeared and the DC / DC converter stopped maintaining a high operating temperature.
There are now several rows of horizontal lines at the bottom of the screen and some shivering on the screen that I can't capture in a photo.
And again I come to the marking of the integrated circuit which I cannot decode.
The marking is 2T = 3M 50J.

[R_J]

Re: DELL P2717H 27 inch white horizontal lines on screen

Have you replaced the caps in the power supply? It may be similar to this https://www.edaboard.com/threads/mon...tripes.396774/

[reaper422]

Re: DELL P2717H 27 inch white horizontal lines on screen

I changed them all today, but unfortunately there is no improvement.

[stefan222]

Re: DELL P2717H 27 inch white horizontal lines on screen

Hello, maybe this could be of help (Take a look at the last post):

https://www.eevblog.com/forum/repair/dell-se2416h/

[questore]

Re: DELL P2717H 27 inch white horizontal lines on screen

More likely you problem is VGH not reaching the Gates. Take a look at this video to try solving:
https://www.youtube.com/watch?v=4HFHpzSQfj0

[KontraStarK]

Re: DELL P2717H 27 inch white horizontal lines on screen

You fix this problem? I have the same

[offs3l]

Re: DELL P2717H 27 inch white horizontal lines on screen

I have the same problem with my se2717h. My measurements are identical.
I have a hissing sound too but I am not sure it is from IC. Seeing that changing that not solved the problem with lines on screen, could it be s34 diode or a capacitor?

[offs3l]

Re: DELL P2717H 27 inch white horizontal lines on screen

I have checked the diode but is ok. I get 5.7 at the gates. Is there any posibility to replace the tcon with another similar to recycle the led panel?

Thanks