Dell 2007wfpb power on problem

[selldoor]

Re: Dell 2007wfpb power on problem

Error - sorry

[red23]

Re: Dell 2007wfpb power on problem

also a quick FYI i plugged the screen in and tried to power it on again after re soldering and the various tests and still the same thing flashing led

[red23]

Re: Dell 2007wfpb power on problem

ok i plugged everything together and re checked a few things.

the fuse (white thing close to board connector) is 18.9v on both sides . the connector on the power board now reads 18.9 volts on all the wires except brown

the missing voltage regulator number is 950T65

as per https://www.badcaps.net/forum/attach...7&d=1336881135 they both have the correct voltage.

Thanks for the referral to the other post!

[smason]

Re: Dell 2007wfpb power on problem

Please see this:
https://www.badcaps.net/forum/showth...007#post289258

Ohh! Awesome post, somehow I missed that one in my search.
Explains a lot.

[budm]

Re: Dell 2007wfpb power on problem

Please see this:
https://www.badcaps.net/forum/showth...007#post289258

[selldoor]

Re: Dell 2007wfpb power on problem

Hmm Usb board - there are some monitors that will not work properly when this is not connected during testing but dont know if this is one of them. On that board there is a fuse -please check it and post result.
in pic 5 there are two voltage regulators in the bottom left corner One is a 952T43
- cant read the other one - at U5.
Please read this
https://www.badcaps.net/forum/showthread.php?p=261329 by retiredcaps on how to identify, test and post the results.

[red23]

Re: Dell 2007wfpb power on problem

Ok here is the pictures of the other 2 boards in the case. I assume you mean the square one but i included the USB board just for reference. Re-soldering the ones you pointed out as we speak,

[selldoor]

Re: Dell 2007wfpb power on problem

I think Smason wanted the MAIN board ie the other one that we have no pics of.
As you have posted these there are a few soldering joints I would like you to
check and possible resolder. In addition to the one in the picture there is
D701 in another pic.

EDIT also reflow all the jopints on the transformer T601 which straddles the black line.

[red23]

Re: Dell 2007wfpb power on problem

When i tested the connector i put the black probe to the ground on the power board and also tested from the black connector wire. So i had the Power board and the Inverter board on my desk plugged in to the wall. (Maybe slightly dangerous )

Ive attached better photos of the power board.

Thanks

[smason]

Re: Dell 2007wfpb power on problem

I did some searching on other threads about this model, and according to most of the photos, there aren't any voltages marked on the connectors.
When you measured the voltages on the connector, was the other end plugged in to another board?

I did read where a couple of these monitors (one was Retiredcaps) had shorted voltage regulators on the main board. Might not be a bad idea to test those.
How about a good photo of the main pcb and we can help you test them.

[red23]

Re: Dell 2007wfpb power on problem

"Ok So the ohms test on the fuse is the same as holding the probes together.
Yes?"

Yes

zero voltage on either side of the fuse after it is plugged in. now i just plugged in those 2 boards if that makes difference, i don't have all the boards out of the metal case but i could do if that's what is needed.

[selldoor]

Re: Dell 2007wfpb power on problem

Ok So the ohms test on the fuse is the same as holding the probes together.
Yes?

Next then with the boards powered and connected set your meter on 200vDC
put the black probe on a ground screw or metal casing of a connector and with the red probe check the voltage on each side of the fuse.

[red23]

Re: Dell 2007wfpb power on problem

your right, its 1 when they aren't touching anything and zero when you touch them together, i put them on the fuse and it reads zero.

[selldoor]

Re: Dell 2007wfpb power on problem

I get 18.9 volts on orange yellow green and zero on the rest. if attached a photo but i see no voltages on the front or the back of the board.

The yellow torpedo fuse is good according to the meter reading 1.

Thanks again for the help.

I think1. may mean out of range - open - is that the same as it reads when the probes are not touching anything?

[red23]

Re: Dell 2007wfpb power on problem

I get 18.9 volts on orange yellow green and zero on the rest. if attached a photo but i see no voltages on the front or the back of the board.

The yellow torpedo fuse is good according to the meter reading 1.

Thanks again for the help.

[selldoor]

Re: Dell 2007wfpb power on problem

Didnt notice before as I was looking for a white smd, there is a yellow torpedo fuse on the inverter board pic 2 - meter on ohms - test and post the result.

[smason]

Re: Dell 2007wfpb power on problem

No, on the connector that has the multi coloured wires that go to another board.
Looking for markings like 5v 12v etc.

[red23]

Re: Dell 2007wfpb power on problem

"Are there voltages marked on the connector on the power supply?"

so you mean the 250Volt marked in the attached picture by the fuse?

"If so, lets measure them each one referenced to ground. So meter on DCV whatever range is higher than the highest marked voltage, red on the voltage we're measuring, black on gnd."

red on the fuse ?

Check that you have put the caps in the right way round - what make did you use? Caps are on correctly G-Luxon is he make

[selldoor]

Re: Dell 2007wfpb power on problem

Check that you have put the caps in the right way round - what make did you use?

[smason]

Re: Dell 2007wfpb power on problem

OK, let's think this through a bit.

Are there voltages marked on the connector on the power supply?
If so, lets measure them each one referenced to ground. So meter on DCV whatever range is higher than the highest marked voltage, red on the voltage we're measuring, black on gnd.