Illyama Prolite 2407HDSD 2s to black

[BertusBeensteen]

Hello everyone,

I'm trying to fix an Illyama Prolite 2407HDSD that has a backlight/inverter problem.
When I turn the monitor on, it works good for a minute or so, then it turns to black, but the power led is still blue (on)(orange is standby).

As mentioned, the backlight starts up as normal, but after a while it turns off.
All the caps seem fine to me on first sight, so i need some help to find the faulty components.

I have a multimeter at my disposal (analog i believe)
Little electronics knowledge, but i understand a lot when explained.

The two black blocks (transformers?) on the powerboard give the same readings, so i suppose they are fine.
The bridge rectifier measures 230 AC, and 322 DC, so thats fine as well i suppose.

Here are some pics i just made:
from left to right: 1 power/inverter board back, 2 power/inverter board front, 3 video board back, 4 video board front, 5 both in housing, 6 powerboard big cap closeup, 7 cap closeup, 8 cap closeup.

[selldoor]

Re: Illyama Prolite 2407HDSD 2s to black

Welcome to the forum - pictures and description good- thanks.
Not the best make of caps may need changing even if they look good.
Are the readings from the transformers EXACTLY the same.
When the back light has gone off can you still see a very dark picture of the source
use a vivd picture on the pc and perhaps shine a flashlight on to the screen at different
angles.
Do you have access to any spare ccfl bulbs - a broken screen -or a working screen you can try these bulbs in.

[ben7]

Re: Illyama Prolite 2407HDSD 2s to black

'Elite' brand capacitors tend to dry out, so seeing them next to a heatsink, I'd think they would get cooked there.

Try measuring the voltages on all output rails, and see if any are off.

[BertusBeensteen]

Re: Illyama Prolite 2407HDSD 2s to black

Thanks for the quick replies!

Welcome to the forum - pictures and description good- thanks.
Not the best make of caps may need changing even if they look good.
Are the readings from the transformers EXACTLY the same.
When the back light has gone off can you still see a very dark picture of the source
use a vivd picture on the pc and perhaps shine a flashlight on to the screen at different
angles.
Do you have access to any spare ccfl bulbs - a broken screen -or a working screen you can try these bulbs in.

The readings are not exactly the same: 0.482 on one, and 0.489 on the other, between pin 1 and 2, between all the other pins i get 0.001

I have acces to a laptop lcd screen (both the screen and ccfl working) , tried it on all the 4 ccfl outputs, but behavior is the same.
I also have a Samsung 205BW that is working correctly, that i can take apart.
Haven't tried the bulbs from the 2407hdsd on the laptop yet, but i suspect they work, will try it tomorrow.

'Elite' brand capacitors tend to dry out, so seeing them next to a heatsink, I'd think they would get cooked there.

Try measuring the voltages on all output rails, and see if any are off.

With output rails you mean the separate ccfl connectors?
Replacing the capacitors either way can't hurt i guess, wil get new ones on monday.
What about the big one?


Sometimes the screen goes to black in 2 seconds, sometimes it takes op to 10 minutes, and sometimes, it just starts up a bit dim, and then goes of after 2 seconds.
turning the monitor off and on real quick usually makes it take 10 minutes again. So my guess is that the startup voltage isn't stable enough, and the constant current isn't constant either.

Thanks for the help guys, will keep this topic updated once i know more!

[ben7]

Re: Illyama Prolite 2407HDSD 2s to black

Thanks for the quick replies!



The readings are not exactly the same: 0.482 on one, and 0.489 on the other, between pin 1 and 2, between all the other pins i get 0.001

I have acces to a laptop lcd screen (both the screen and ccfl working) , tried it on all the 4 ccfl outputs, but behavior is the same.
I also have a Samsung 205BW that is working correctly, that i can take apart.
Haven't tried the bulbs from the 2407hdsd on the laptop yet, but i suspect they work, will try it tomorrow.






With output rails you mean the separate ccfl connectors?
Replacing the capacitors either way can't hurt i guess, wil get new ones on monday.
What about the big one?


Sometimes the screen goes to black in 2 seconds, sometimes it takes op to 10 minutes, and sometimes, it just starts up a bit dim, and then goes of after 2 seconds.
turning the monitor off and on real quick usually makes it take 10 minutes again. So my guess is that the startup voltage isn't stable enough, and the constant current isn't constant either.

Thanks for the help guys, will keep this topic updated once i know more!

NOO don't measure the voltage at the ccfl connectors, it will be too much voltage for your dmm!

Yeah, sounds like a classic case of dry caps!

[BertusBeensteen]

Re: Illyama Prolite 2407HDSD 2s to black

The monitor is working perfectly for about 15 minutes now.
Just seeing how long it will take for it to go black again.

So the caps are suspect number one?
I will replace the small ones on monday, what about the big one?
I hope the local shop has them so i can replace them all.

Again, thanks a lot! Where can i buy you guys a beer?
I will be frequenting these forums more often i guess

[ben7]

Re: Illyama Prolite 2407HDSD 2s to black

So the caps are suspect number one?
I will replace the small ones on monday, what about the big one?
I hope the local shop has them so i can replace them all.

I would just do all the smaller ones, and leave the big brown one for now. Make sure you get 105*C rated low ESR caps too!

[tom66]

Re: Illyama Prolite 2407HDSD 2s to black

I have seen my workplace using these monitors almost exclusively.

Given the build quality I expect they'll be throwing these out in a couple of years...

Check the supply voltage going to the inverter (usually 12V), see if it drops out.

[selldoor]

Re: Illyama Prolite 2407HDSD 2s to black

"Replacing the capacitors either way can't hurt i guess, wil get new ones on monday."

You should get Low ESR caps Panasonic FR FM or FC

What about the big one?"

Unless it is bulging leaking or damaged it is not usually necessary.

"With output rails you mean the separate ccfl connectors?"

Test the voltages on the other connector on the power board with the Blue green yellow and white wires. Please do it when it is on if you can and also
when in fault.

[BertusBeensteen]

Re: Illyama Prolite 2407HDSD 2s to black

The local shop does not have the Panasonic caps, so i ordered them online, should be here tomorrow.
Monitor worked for hours yesterday, until i turned it off.
Today, it is still working since 8:30.
I'll still replace the caps to be sure though.

[BertusBeensteen]

Re: Illyama Prolite 2407HDSD 2s to black

I replaced the caps, and now, one week later, the screen still works like a charm.
Thanks for the help and rapid response!

[tom66]

Re: Illyama Prolite 2407HDSD 2s to black

I recapped mine completely with Panasonic and Rubycon; its main problem was bad solder joints but clearly these crappy caps don't bulge either!