Hello people!!

I was thinking I might find some help here, so I try to post my problem, maybe someone could help me, as I'm already desperate.

My monitor has a "RGB-component" leak since a while. It loses mostly the red one, so that the image looks blue-greenish. It comes back sometimes, or it just flickers for a few seconds in the normal state and then it disappears again (but not necessarily every day). It behaves as if the cable wouldn't be correctly connected to the VGA card - which of course is not the case.
However it goes on my nerves because it lookes like the old IBM black/green monochrome monitors when this happens, so I could say good bye to my colors .

But when I open the monitor's OSD-Menu all the colors are shown (on the menu) so this leads me to the conclusion that it might be a problem with the signal processing that comes from the VGA, although I tried it on several cards - same result.

Another problem is that the colors are shown only in Windows!!! For example BIOS only shows gray shades on this monitor.

When I open the monitor's case and just take a look - without touching anything!!! - and then mount the case back, it works fine again for a few days, then the problem occurs again.

Could anyone help me with this? I would also be grateful for a schematic.

Thank you in advance!

This can be cause by the signal cable either at the monitor end or at the computer.

Try to flex the cable at either end and see if the alters the problem, also we had a lot of problems with the crimps on the cable at the monitor where the signal cable enters the PCB's.

Rich

Flexing the cable was the first thing I did when I noticed the malfunction. It didn't bring any result, as already mentioned.
The bad thing is that I don't know what should I start with.
Suppose I open the case again. OK, but what should I do next? It's clean inside, so there's nothing to clean anymore (dust or something like that).
The funny thing is that it works again when the case is removed. I don't know for how long because I always put it back after I took a look inside.
Besides that, even if I hit it (as Paul did) nothing happens, so gave up the idea.
It's very important to mention that the OSD colors are correct, even if the image leaks one component.

Any other clues, please?

Hi does your monitor only have 1 signal input cable and does it connect to connector CN401.

If so there is very little circuit before the OSD signals combine with the video signals.

In this case I am inclined to still think it is the cable it maybe that the internal cable clamp is stopping the flexing showing up the fault.

Yes, there is only one cable which cannot be pulled out from the monitor (it's soldered), it only connects to the VGA.
I already verified the cable and why does it work when I open the case? And even afterwards keeps it working for a few hours - up to a few days and then it starts over losing color.

You were right, Richard! I opened the case again and tried to shake the thin wires that come out from the cable and go into the plastic connector in the tube's PCB part. One of these wires have a weak contact. Anyway I'm so happy now... At least I can tell now I localized the problem.

Thanks again!

Hi thats good I was trying to think of a way to convince you to do that.

Rich