Pink tint on screen Dell U2312HM - Page 1
Forum section: electronics / repair

author: onurz
author_rank: Newbie
timestamp: May 09, 2020, 08:32:13 pm
content: I just saw thishttps://www.eevblog.com/forum/repair/dell-u2312hm-power-supply-board-repair/. What a coincidence, 2 different problem with same monitor in one day.I have a Dell U2312HM that I haven’t used for few years. Last time I used it was fine. Now I need to use again so I plugged it in and I saw there are some disturbance on screen. There is a pink tint on right half side of the screen, some waves going on there as welland some texts have reddish shadow. When I checked internet I saw some people experienced similar problem with this panel.Here is picture of another user, mine looks similar but my pink tint is on the right side of the panel.I tried record a video to show the waves but it is not seen on the recorded video. These waves hint me that may be some capacitors are gone bad on power board?I tried different inputs, same problem. While no input, monitor menu also shows same problem.Is this a unrepairable panel problem or is it related with power or display boards? I can try to repair boards but I need a guesstimation. People say that it is caused by long term usage but mine wasn’t used much and had been siting for a long period.

author: pbarton
author_rank: Frequent Contributor
timestamp: May 09, 2020, 09:15:04 pm
content: CCFL backlight tube fault.Replacing the original CCFL tube with LED strips, seems to be popular.

author: onurz
author_rank: Newbie
timestamp: May 09, 2020, 09:22:47 pm
content: Does CCFL tube failure cause wave ripples as well?

author: keymaster
author_rank: Regular Contributor
timestamp: May 09, 2020, 09:34:09 pm
content: this screen make use of leds, no ccfl.

author: onurz
author_rank: Newbie
timestamp: May 09, 2020, 09:37:06 pm
content: Yes I just checked tftcentral."The Dell U2312HM utilises an LG.Display LM230WF3-SLD1 e-IPS panel""The U2312HM uses White-LED (W-LED) backlighting."

author: Miti
author_rank: Super Contributor
timestamp: May 10, 2020, 11:04:04 am
content: White LED cannot turn pink. My bet is, if it is indeed LED, there’s a strip of RGB LEDs on both sides and one colour or colour driver is bad on the left side.However, this is a typical CCFL gone bad symptom, including the waves.

author: dersonf
author_rank: Newbie
timestamp: July 18, 2021, 08:38:18 pm
content: Hello guys, I have exactly the same problem. This monitor is with me for a long time, I purchased it from a company where a have been worked after finished the services in Brazil since 2016.The monitor shows this problem one year ago and vanished and back to normal, nowadays problem back again, I disassembled and check all connectors and flats and all seems very good. I don't took out the power board just the controller.The image at right side is kind of blurred too.Someone found out a way to fix for yourself replacing some component like capacitors, resistors, transistors or even some of two boards?Thanks for anything.

author: dersonf
author_rank: Newbie
timestamp: August 29, 2021, 08:21:22 pm
content: I took out the capacitors from the video board next to the video connector and all capacitors are working fine.