Dell 2408WFP white screen

[caykroyd]

See picture below... It is not pure white.... I can see the display, but there is no color only "shades of white".

I have searched the forum, but haven't seen this problem. I have taken the monitor apart thanks to budm's teardown pics. I do not see any visible signs of damage. Based on the problem, where should I start to look? I'm ready to probe nodes and debug. I just don't know where to start.

Thanks,
Craig

[1supertech]

Re: Dell 2408WFP white screen

Check LVDS cable for proper connection to Tcon board test fuse on Tcon (f1)
also make sure all capacitors on main board are ok . If all test ok you may have a bad
lcd panel or tcon

[budm]

Re: Dell 2408WFP white screen

That is the Gamma voltage ref problem on the T-CON board. Pictures of the T-CON?

[caykroyd]

Re: Dell 2408WFP white screen

Ahhh... Just realized there is another board.... The TCON board below the main board. I will expose that board after work and take and upload photos.

Thanks.

[budm]

Re: Dell 2408WFP white screen

Similar to TV problem:
https://www.badcaps.net/forum/showth...S15#post322816

[caykroyd]

Re: Dell 2408WFP white screen

Finally got to exposing the T-con board. See attached photo. I don't see any problems popping out at me.

Any ideas on the steps to debug this?

[budm]

Re: Dell 2408WFP white screen

There is no test points for the Gamma voltage reading that I can on this T-CON board. I do not know what else you can do beside trying the new board

[caykroyd]

Re: Dell 2408WFP white screen

Thank you. I have two choices...find a new T-Con board or swap T-con board from my other monitor.

The problem..... My other monitor also has problems. 50% of the time if has the problem shown in the attached photo. It seems to come with more use (maybe heat). I'm not sure even how to describe the problem.

It's not consistent vertical red lines. some times patches of green and sometime patches of the correct color.

If this is also the T-con, then obviously a swap wouldn't help, but if it is something else, then with two bad monitors, I can at least make one good one.

Thanks for the help.

-- craig

[caykroyd]

Re: Dell 2408WFP white screen

Finally received a new T-Con board. Well, not new, but supposedly a good, working one.

I still have the exact same problem. Overly white screen. Any other thought of what to check? I think I've check all fuses.... May have missed a couple....

Thanks,
Craig

[Lumberjack777]

Re: Dell 2408WFP white screen

Ok Craig, I would use both monitors to troubleshoot this problem. Try dropping that "new" T-Con board into the 2nd monitor. That 2nd one (post #8) definitely looks like T-Con. When you have them both apart; carefully remove the LVDS ribbon from the 2nd monitor and attach it to the one with the semi-white screen. See if that fixes the picture. If it doesn't then you may have a main board problem. But that T-Con should fix the problem in that 2nd monitor.
I have repaired 3 of these. 2 of them were T-con, and 1 was a main board. Seems to be a common problem with this model.

[dhansen]

Re: Dell 2408WFP white screen

Craig,

Did you ever resolve your problem? I'm having the same issue on my Dell 2408WFP (white/washed out screen). I'm trying to debug the issue, and having about the same luck (so far) as you have in this thread.

[selldoor]

Re: Dell 2408WFP white screen

Thread is a bit old and craig has not posted in anything since.
Does your screen come on with correct colour then turn white or is it white from start.
Have you tried a factory reset or colour /brightness adjustment - do the controls do anything even if not what you want?

[dhansen]

Re: Dell 2408WFP white screen

It comes on white from the start. I already tried a factory reset to no avail. I haven't tried adjusting the colors, and I currently have it taken apart, so I'll have to reassemble it and try that.

[selldoor]

Re: Dell 2408WFP white screen

OK well if you have it apart can you post some good clear pictures of your boards?

[dhansen]

Re: Dell 2408WFP white screen

I've attached images of all the boards.

[selldoor]

Re: Dell 2408WFP white screen

Thanks - My worry is that a previous poster said replacing the tcon did not help. Maybe he got a faulty replacement?
On the tcon there is a white fuse - next time its together can you test the voltage at each side of the fuse with respect to chassis ground.
There are also 4 voltage regulators on that board IC19 IC21 IC7 and IC9 can you test the voltage on each pin of each one with respect to ground and also the name of each IC.
Also there is a chip at IC20 - what is the part number on that.
Finally bottom right radiating from the socket the board looks discoloured brown as against green - is that just the picture or is it really like that.