DELL 2405fpw

[Mirage00]

Re: DELL 2405fpw

Hi,

The F1-F4 boxes are not fixing points. Its odd, they are just square boxes. Not sure exactly what they are.

I didn't check the torpedo fuse, but I thought if the display is turning on and all button functions work, then the issue would not be power related on the power supply?

The L shaped board is just the USB/Media card dock. It's not part of the main board circuitry. If you still want a pic, I will need to take one.

[selldoor]

Re: DELL 2405fpw

Hi - in each corner of the main board there is a F1 to F4 designation are there any fuses there or is it just a fixing point? Also on the Power Supply there is an Orange pico torpedo fuse - has that been checked. I dont know much about circuits so its just a case of see a fuse check it. There are also 2 on the inverter board. Can you do a close up pic of the L shaped board - just for completeness.

EDIT
Also can you do a pic of the back of the main board if there are any component on it.

[Mirage00]

Re: DELL 2405fpw

Here ya go

[retiredcaps]

Re: DELL 2405fpw

I have a second 2405fpw and the OSM displays when you press the menu button regardless of it receiving a video signal (computer off)

Not all monitors have that feature which is why we always ask for a computer to be hooked up.

Can we get an overall backside shot of the lcd? I can't quite tell the relationship of all the boards with the different orientations. I would like to see how all the boards are connected to each other.

[Mirage00]

Re: DELL 2405fpw

Let's eliminate the obvious.

1) Have you tried a different computer?

2) Have you tried a different VGA or DVI cable?

3) Have you tried all the input ports?

4) Are you using known working computer and VGA/DVI cable?

Yes to all. As I mentioned the On Screen Menu does not display. I have a second 2405fpw and the OSM displays when you press the menu button regardless of it receiving a video signal (computer off).

[retiredcaps]

Re: DELL 2405fpw

Nothing shows on the LCD.

Let's eliminate the obvious.

1) Have you tried a different computer?

2) Have you tried a different VGA or DVI cable?

3) Have you tried all the input ports?

4) Are you using known working computer and VGA/DVI cable?

[Mirage00]

Re: DELL 2405fpw

1) Does your laptop wallpaper show up on the lcd?

2) If not, is the screen just white?

Nothing shows on the LCD. The screen is a greyish black, the backlight is on because I can see the ccfl lit. Here is a pic of the monitor, its hard to see ( I was holding it up) but it shows the lights and buttons working at the bottom and the screen backlight on.

[retiredcaps]

Re: DELL 2405fpw

Wrt to post #27, can you get a picture of what is going on so we can see? Make sure a computer is hooked up to it.

[retiredcaps]

Re: DELL 2405fpw

Some sort of signal is being detected because when the backlight turns of after 30-40 seconds, if I toggle the monitor output on my laptop that is connected to the 2405fpw the backlight turns back on again.

1) Does your laptop wallpaper show up on the lcd?

2) If not, is the screen just white?

[Mirage00]

Re: DELL 2405fpw

I really appreciate your help. Thank you

[retiredcaps]

Re: DELL 2405fpw

part number F5305S
I-R 506C
Pin #1 18.30
Pin #2 0
Pin #3 18.66

part number FR9024N
I-R 452G
Pin #1 18.44
Pin #2 5.14
Pin #3 18.70

I will have to look up the 2 above. I'm not sure about those readings.

part number H183
950T65
Pin #1 3.29
Pin #2 0
Pin #3 2.48

part number H185
952T43
Pin #1 0
Pin #2 1.8
Pin #3 3.28

The two above are working perfectly. The first is a 2.5V regulator. The second is a 1.8 regulator.

See

http://pdf1.alldatasheet.com/datashe.../G950T65U.html

http://pdf1.alldatasheet.com/datashe.../G952T43U.html

[Mirage00]

Re: DELL 2405fpw

Here are the new readings with everything hooked up and power on

part number F5305S
I-R 506C
Pin #1 18.30
Pin #2 0
Pin #3 18.66

part number FR9024N
I-R 452G
Pin #1 18.44
Pin #2 5.14
Pin #3 18.70

part number H183
950T65
Pin #1 3.29
Pin #2 0
Pin #3 2.48

part number H185
952T43
Pin #1 0
Pin #2 1.8
Pin #3 3.28

[Mirage00]

Re: DELL 2405fpw

Ok fuse voltage on each side of fuse is .34 on each side

[Mirage00]

Re: DELL 2405fpw

OK, let me get the voltages with everything hooked up

[Mirage00]

Re: DELL 2405fpw

part number F5305S
I-R 506C

part number FR9024N
I-R 452G

part number H183
950T65

part number H185
952T43

[budm]

Re: DELL 2405fpw

And hook it to running PC also, otherwise it will go into standby mode.

[retiredcaps]

Re: DELL 2405fpw

No the lcd is unplugged. Does it need to be on? If so, can I plug it in and turn it on without the tcon board connected (I took it out for pictures and testing)

Yes, power has to be on for all voltage measurements. Let's start again with the voltage measurements on t-con and then the 4 voltage regulators (with all the part numbers on the IC).

Put your multimeter on 20V DC.

[budm]

Re: DELL 2405fpw

I know that the monitor detects the signal from the PC OK, but the main board is not turning on this transistor to supply the voltage to the T-CON board, that what we will have to trace out the B+ line from the T-CON connector to see where it goes to. There may be another fuse on the main board also, I cannot find any service manual for this monitor yet.
It will have to be troubleshoot down to the component level at this point.

Well, after reading post 16, I may have to disregard my troubleshooting method until we get more info.
"No the lcd is unplugged"

[retiredcaps]

Re: DELL 2405fpw

If the IC has more than one line on its part number, please list them all. For example H183 has 950T65.

[Mirage00]

Re: DELL 2405fpw

Please redo the two above with your multimeter on 20V (twenty). Do you have power on and lcd plugged in?

No the lcd is unplugged. Does it need to be on? If so, can I plug it in and turn it on without the tcon board connected (I took it out for pictures and testing)