Dell 2007wfpb power on problem

[red23]

Re: Dell 2007wfpb power on problem

ok so i did that, replaced all the caps on the power board except the large one. Re assembled and its doing the same thing except this time it didn't give me any thing on the screen just the Power LED and source 2 flashes at about a 5 second interval.

Thanks for all the ideas to try guys, i would say i'm an intelligent beginner so all the help is greatly appreciated.

any more ideas ?

[smason]

Re: Dell 2007wfpb power on problem

If it was mine, I'd replace ALL the crap caps on the power supply (except the large one)
Those are CRAP caps, and just 'cause they're not bulging doesn't mean they aren't causing problems.

[red23]

Re: Dell 2007wfpb power on problem

yes so, if its is unplugged from the wall for a period of time it seems to come on and you get the dell logo as it boots up and works normal if connected to a PC. But after the PC puts it to sleep it wont come out of sleep it just flashes the LED as if its trying to power on and you hear the relay clicking. Same thing if it is unplugged from a PC source and just plugged into the wall socket. its like it gets warm and stops working but works when its cold.

[selldoor]

Re: Dell 2007wfpb power on problem

I think I misread your first post.
Are you saying if the monitor is unplugged for a while then set up it works? is it connected to a pc?

But then if you leave it plugged in but switch it off then back on it does does not come on.

I read it that you had a single flash of the backlights but now wonder if you mean only the power led flashes on then off then on every 8 seconds or so

[red23]

Re: Dell 2007wfpb power on problem

About to try and check these mosfets, but here is some pictures.

[jetadm123]

Re: Dell 2007wfpb power on problem

Transformer readings look ok. Check mosfet using this guide, start at post #13, step 2:

https://www.badcaps.net/forum/showthread.php?t=10419

A photo of the entire inverter board would be nice.

[red23]

Re: Dell 2007wfpb power on problem

Thanks for the reply! so i checked the resistance on the

T801
S1-S2 = 1076
S3-S4 = 1066

T802
S1-S2 = 1070
S3-S4 = 1062

T803
S1-S2 = 1073
S3-S4 = 1068

I am not sure how to check the mosfet

[selldoor]

Re: Dell 2007wfpb power on problem

Do the inverter tests mentioned in this post
https://www.badcaps.net/forum/showth...light=2007wfpb

[red23]

Hello all and thanks for this forum, clearly allot of useful information on here.

SO i have a Dell 2007wfpb which works intermittently but less and less lately. I have considered just binning it and buying a new monitor for 100 bucks but i don't like wasting things so here i am.

What is happening is that when the monitor has been off for a long time, unplugged you can turn it on and get the dell logo to come up. if you leave it plugged in and then try to turn it on it goes into this loop of the green LED lights for power and source (1only) flash on then off with about 5-8 seconds in between and you here a relay clicking. it never comes out of this loop and never powers on. I have pulled it apart and looked at the different boards and there is no obvious signs of damage or bulged or leaking capacitors. I checked the fuse on the power board and somewhat checked the capacitors on that board with a multi meter and they all start to take a charge. I have attached the photos i have of the power board. Any suggestions are appreciated.