Dell monitor 2007FPb will not stay on

[ngutman]

I have a Dell monitor 2007FPb connected to my laptop using a VGA cable. The monitor stays ON for about 30 seconds then goes OFF, comes back ON for 30 seconds, goes OFF and so on.
It did same when it was connected to another computer via a DMI cable.
What might be the problem and how to fix it?
Thanks,
Nathan

[Davi.p]

Re: Dell monitor 2007FPb will not stay on

Hi, what it does with the led lights? Try to open it and make it work without covers, when it is warm (switched off since 1 min) use an hardryer on all the psu board to warm it up then power on, does it stay on? If yes retry warming the main logic board.. if yes retry on the tcon board..

[ngutman]

Re: Dell monitor 2007FPb will not stay on

The lights come off and come back on when the monitor restarts.
What is the warming suppose to show?

[vinceroger69]

Re: Dell monitor 2007FPb will not stay on

if there are bad capacitors on the boards heating them can tempory lower the esr and some times the psu etc will work.

[Davi.p]

Re: Dell monitor 2007FPb will not stay on

Update: if the leds came off maybe psu outputs goes low when mon. stops, try to test them for sure, if yes you can concentrate the heating job whithin this board. The only components i think are sensible to the heat are alluminium caps and NTC (or PTC i don't remember).

[ngutman]

Re: Dell monitor 2007FPb will not stay on

Can someone kindly tell me what PSU board, TCON bord, NTC or PTC stand for.
How do I identify those boards when I open the monitor. Are they labeled in any way?
Thanks,
Nathan

[Davi.p]

Re: Dell monitor 2007FPb will not stay on

psu board is the bigger board that you see inside and has the 220/100VAC connector, NTC is a small round/flat component with 2 legs coloured in black or green near the previous connector, the tcon is another board but it doesn't matter now.

[newtothis]

Re: Dell monitor 2007FPb will not stay on

the PSU is the Power Supply Unit, Will have a large capacitor on it. Its the one the has a cable that goes to your mains plug

Even for me reading this it is confusing :S Sorry Davi.p

Open the back up and take a picture of the entire back so we can see all the boards and connectors, then take one of each board closer up.

[ngutman]

Re: Dell monitor 2007FPb will not stay on

I opened it up and see the PSU but what is the trick to take it out. I removed the three screws and can wiggle the board but it will not separate from the power socket and it does not come out with the socket.
So how do I get it out?
The board is 5D*L2J02001 0211 612 GUND48D 297741 if this means anything to you.
Photo of all the boards is attached. I point to the PSU with a red arrow.
Thank you for helping.
Nathan

[Davi.p]

Re: Dell monitor 2007FPb will not stay on

There's a black plastic clip well visible, with a flat screwdriver you have to press it from the bottom side until it pops out in the upper side (as from your picture)

[ngutman]

Re: Dell monitor 2007FPb will not stay on

Thanks I got it. Am able to see all components now. Don't see any leaking or bulging capacitors. From reading this forum I understand that the capacitors on the PSU board are often the problem. Should I just replace the five capacitors and hope for the best? The problem was that the monitor was cycling on/off about every 30 seconds.
Photo of three board components is attached. The fourth little board has just two USB ports and two more ports which I don't recognize.
Thanks again,
Nathan

[Davi.p]

Re: Dell monitor 2007FPb will not stay on

Can you make me a new photo of a particular area around IC702? it's a 3 leg smd chip on the PSU board in the bottom side near the big transformer.. i have to read the markings on the resistors and see their position..

[ngutman]

Re: Dell monitor 2007FPb will not stay on

Is this the area that you are looking for?
Nathan

[Davi.p]

Re: Dell monitor 2007FPb will not stay on

NO, i mean here:


The reason for why i asked this is that i want to find the normal output voltage so you can test the monitor with an external psu, but if you feel not good to do this type of test try to buy those capacitors (low ESR types) and hope, i don't like that way..

[budm]

Re: Dell monitor 2007FPb will not stay on

The power supply is a single output power supply, you can verify the DC output right at the two leg of the cap C711, it should have about 19VDC when the monitor is plugged in, the power supply is an always on power supply. There are Buck regulator switching power supplies on the USB board for dropping the 19V down to 5v, 3.3V, etc.
So monitor the 19v output.
There are more than one version of this 2007 monitor.
Your version is not the same but still uses the same setup.
http://s807.photobucket.com/user/bud...?sort=3&page=1

[Davi.p]

Re: Dell monitor 2007FPb will not stay on

So budm, we want assume that the psu has 19v? I wanted to tell him to search for a laptop psu with 19v to supply the monitor..

[budm]

Re: Dell monitor 2007FPb will not stay on

Yes, it is 19VDC, you will need about 4A minimum (monitor spec is 55Watts, so use higher rating for head room)

[ngutman]

Re: Dell monitor 2007FPb will not stay on

I replaced the 5 capacitors on the PSU board. The monitor performed a little better but still continued rebooting every few minutes. Eventually it went off and it will not turn on. Pressing the power button does nothing.
Is there anything that I can still do to revive it or is it ready for the landfill?
I posted the PSU board. I am just an amateur tinkerer so please be specific about what component to replace and where to get it.
Thank you all for holding my hand so far.

[selldoor]

Re: Dell monitor 2007FPb will not stay on

What make/series caps did you use - they are the same color in that pic as in the first one?

[ngutman]

Re: Dell monitor 2007FPb will not stay on

The photo shows the old capacitors. I got the new ones from a reputable US company.
Nathan