FPD2485W - Replaced Capacitors and still not backlight

[desitdt]

Hi there I was having a problem with my FPD2485W monitor where it would no nothing, no lights, no menu lights, no sound other than a sparking sound, and ordered the capacitor replacement kit from LCDAlternatives:

http://lcdalternatives.com/LCD-Repai...-P1700081.aspx

After Replacing the 12 capacitors the unit powers up, i get menu lights, startup sound, but no backlight. If i hold a flashlight to the monitor in a dark room i can see the gateway logo so the lcd is working. Could a fuse be blown or something? Thanks for the help.

[budm]

Re: FPD2485W - Replaced Capacitors and still not backlight

That means you may still have problem with the backlights inverter board. Please upload good clear pictures of the whole chassis and each board so we can see what has on this revision of your monitor, make sure to use attachment for uploading the pictures.

[desitdt]

Re: FPD2485W - Replaced Capacitors and still not backlight

which board is the backlights inverter board?

[desitdt]

Re: FPD2485W - Replaced Capacitors and still not backlight

Here are the pictures of the chassis and boards.

[budm]

Re: FPD2485W - Replaced Capacitors and still not backlight

Please edit your post and use GO ADVANCED to upload the pictures, use the attachment function. posting in line takes a long time to load the page.
The inverter board in the one on the right with a bunch of small high voltage transformers.

[desitdt]

Re: FPD2485W - Replaced Capacitors and still not backlight

I think i found the culprit but i am not sure. I did this fix about a year ago and now i cannot remember how this happened. Any way to test and see if this solder joint is ok?

[desitdt]

Re: FPD2485W - Replaced Capacitors and still not backlight

Is there any way to fix that solder job? the pad seems like a burnt it off.

[retiredcaps]

Re: FPD2485W - Replaced Capacitors and still not backlight

Is there any way to fix that solder job? the pad seems like a burnt it off.

Use your multimeter and see what has continuity to those capacitor legs and then run an insulated jumper wire to it.

[desitdt]

Re: FPD2485W - Replaced Capacitors and still not backlight

Is the white component in this picture (circled in red) a fuse? i am not getting continuity across it.

I tested and i am getting continuity from the messed up diode to a leg of the other diode. could i just add a wire like shown in the second picture.

[selldoor]

Re: FPD2485W - Replaced Capacitors and still not backlight

1 Yes its a fuse


2 No idea what you are talking about "Diode"?

[desitdt]

Re: FPD2485W - Replaced Capacitors and still not backlight

Sorry i meant capacitor. Is there more than one fuse on the board? There seems to be 2 for each harness on the inverter board. Or is there only one fuse?

[selldoor]

Re: FPD2485W - Replaced Capacitors and still not backlight

Is there more than one fuse on the board?

You are in the best position to check? That one is labelled "F1" if there are others they will be labelled F2 F3 and so on.


Are you sure that cap needs wiring, that leg MAY go through the board
to a trace on the other side? You will need to take the board off or at least
take the screws out and tilt it to check.

Your connection looks much the same as this one
http://assets.shopjimmy.com/media/ca...811400810r.jpg

[desitdt]

Re: FPD2485W - Replaced Capacitors and still not backlight

I asked if there was more than one fuse because i tested everything i thought could be a fuse and did not have continuity through any of them. I'm not sure what you mean by the second part of your post? there are pictures of both sides of that solder joint on the capacitor leg up above.

[desitdt]

Re: FPD2485W - Replaced Capacitors and still not backlight

Just some updates.

I figured out fuse F1 was blown. when i had the monitor apart, everything worked perfectly. I put everything back togeather and to my dismay nothing worked, no power, no lights, nothing.

It turned out to be that the leads from the two capacitors that i replaced on the inverter board were too long and shorting to the case, i trimmed them up and now everything works perfect.

To anyone attempting this fix, I STRONGLY urge you to never disconnect the front bezel from the screen. Anything you need to do can be done just by pulling the back off and removing the boards, i took that ribbon cable out and damaged it where the traces touched each other. then i had to sit for about an hour with some fine tools and get the traces relatively straight again before the from lights and sensors would work.

[selldoor]

Re: FPD2485W - Replaced Capacitors and still not backlight

Pleased for you - I had missed that bottom board picture altogether -sorry
still would not have spotted the legs were too long. They are often surface soldered on those type of boards. - Well done.