Acer AL2416 AL2416W 24" 1920x1280 LCD Monitor

[Toasty]

Re: Acer AL2416 AL2416W 24" 1920x1280 LCD Monitor

Yes, that cap does look scorched. Opened it in pic program and brightened it up.

Although the scorched cap would indicate another problem, the main course of action with these is to replace the 10 inverter board caps first. They are/can be non-bloat fails. With luck, they didn't take out the FETs.

Don't get any fancier than the originals, spec wise. In other words, if PW or FC are close, use them. Don't go to an FM or KZE quality just because they are better specs. You'll may end up with the same problem or creating a new one. That chip seems to be -very- picky (sensitive). I'd like to find a way to "fool" it long enough to get good readings.

Toast

[PlainBill]

Re: Acer AL2416 AL2416W 24" 1920x1280 LCD Monitor

Yes, that cap does look scorched. Opened it in pic program and brightened it up.

Although the scorched cap would indicate another problem, the main course of action with these is to replace the 10 inverter board caps first. They are/can be non-bloat fails. With luck, they didn't take out the FETs.

Don't get any fancier than the originals, spec wise. In other words, if PW or FC are close, use them. Don't go to an FM or KZE quality just because they are better specs. You'll may end up with the same problem or creating a new one. That chip seems to be -very- picky (sensitive). I'd like to find a way to "fool" it long enough to get good readings.

Toast

What is the controller IC? I didn't see it listed anywhere in the thread.

PlainBill

[Toasty]

Re: Acer AL2416 AL2416W 24" 1920x1280 LCD Monitor

I've got to check some pics and notes. I am not sure if I noted it's number. I do know I got the sheet somewhere because I tracked down some voltages and the pin that monitors the HV circuits. There's another thread in here (IIRC) on this monitor.

[Toasty]

Re: Acer AL2416 AL2416W 24" 1920x1280 LCD Monitor

What I'm finding is

O2 Micro OZ964

PDF attached


What is the number of the one on this board, wenter?


Toast

[Toasty]

Re: Acer AL2416 AL2416W 24" 1920x1280 LCD Monitor

Ah-ha. From other threads, OZ9925GN.

I've requested datasheet from 02 Micro.

Someone is selling them on eBay. I've asked them if they have a sheet.

Found attached hand drawn circuit diagrams (not the same monitor) from a Russian site. Diagram of chip and circuitry around it.

Also found an old catalog with this chip in it. Extracted the page and posted it here as a single PDF.

Toast

[wenter]

Re: Acer AL2416 AL2416W 24" 1920x1280 LCD Monitor

I have checked all CCFL's one by one. The flash was about same intensity on all of them.

Today I went to MarVac store (radio parts) and they found me some caps for inverter. I have replaced all of them, and nothing had changed.

Monitor turns on, shows Logo for a second, and nothing on screen. Power LED remains green.

Kids went to bed, so it was silent in the room and as I was turning it on and off I have noticed something.

When I press power button there comes little buzzing sound from red circled area at the same time lamps are turning on. After a second I can here the click from the same area and lamps are turned off.

Can it be the case, and not the inverter itself?

[hernan_perez_br]

Re: Acer AL2416 AL2416W 24" 1920x1280 LCD Monitor

Hi Guys, I am new user in this excellent forum.
Yesterday a friend gave me a faulty Acer AL2416w LCD monitor for free. When I power on it shows the 'acer' logo and after 2 o 3 seconds the screen is just black.
I have no idea about electronics but I definetly want to give it a try and fix it by myself (I just have a solder and a multimeter). I was reading the forum and I could open the case and I took some photos.
Could you please give me some instructions what should I do to find the problem?
Thank you very much!!!!!!

[hernan_perez_br]

Re: Acer AL2416 AL2416W 24" 1920x1280 LCD Monitor

Sorry, I forgot to attach some pictures of the video board. Here you are:

[PlainBill]

Re: Acer AL2416 AL2416W 24" 1920x1280 LCD Monitor

Hi Guys, I am new user in this excellent forum.
Yesterday a friend gave me a faulty Acer AL2416w LCD monitor for free. When I power on it shows the 'acer' logo and after 2 o 3 seconds the screen is just black.
I have no idea about electronics but I definetly want to give it a try and fix it by myself (I just have a solder and a multimeter). I was reading the forum and I could open the case and I took some photos.
Could you please give me some instructions what should I do to find the problem?
Thank you very much!!!!!!

1. PLEASE don't attach pictures inline. It slows down loading the thread, seriously inconveniences retiredcaps, and pi55es off the rest of us.

2. Learn to use the Search button. There are at least two other threads for the same monitor, at least one has the same problem, and the solution is given.

PlainBill

[hernan_perez_br]

Re: Acer AL2416 AL2416W 24" 1920x1280 LCD Monitor

Sorry for the photos, do you want me to delete them?.
I did a search, and some problems where in the inverter board and others in the power board.
Could you please just have a quick look to the photos and tell me what do you think the problem is?
When I switch on the monitor, it shows the "acer" logo only for a second or half a second, and then the screen is black but
the power led is always Green, never amber.
I also realised when is switch on, I hear a "click" sound neard one transformer in the middle of the inverter board. Is that normal?

[retiredcaps]

Re: Acer AL2416 AL2416W 24" 1920x1280 LCD Monitor

Sorry for the photos, do you want me to delete them?.

Too late now. You can't edit the thread after 30 minutes after posting.

When I switch on the monitor, it shows the "acer" logo only for a second or half a second, and then the screen is black but
the power led is always Green, never amber.

The possible causes of "2 seconds to black" are in no particular order

1) bad caps
2) bad inverter transformers
3) bad ccfl
4) bad ccfl wiring
5) something wrong in the inverter sense circuitry

Causes 1 - 4 are all discussed in this very thread and the other AL2416 thread.

If you have a multimeter, you can rule out #2 by measuring the inverter transformers (see post #99).

For #1, as recent posts suggest, some have had success changing out the caps on the inverter board (10 of them) with high quality low ESR brands like Panasonic FM.

[hernan_perez_br]

Re: Acer AL2416 AL2416W 24" 1920x1280 LCD Monitor

Thank you very much for your answer.
I will try changing out the 10 caps on the inverter board.
Is it the capacitor I have to order?
http://australia.rs-online.com/web/s...uct&R=4491056#

Thanks you very much!

[retiredcaps]

Re: Acer AL2416 AL2416W 24" 1920x1280 LCD Monitor

T
Is it the capacitor I have to order?
http://australia.rs-online.com/web/s...uct&R=4491056#

As long as the uF, voltage, and diameter match (or smaller in diameter) match the original ones, the Panasonic 100uF 35V FC is a good choice for replacements.

[severach]

Re: Acer AL2416 AL2416W 24" 1920x1280 LCD Monitor

One set of caps on the inverter board is darker than the other set. They started the same color. Heat degrades the plastic and changes the color. Heat also degrades the insides. There's no vent on the top so look for the bungs to be pushed out.

[retiredcaps]

Re: Acer AL2416 AL2416W 24" 1920x1280 LCD Monitor

One set of caps on the inverter board is darker than the other set.

severach's observation is why we always ask for pictures of your particular board. When people post "my board is identical to so and so", I just starting rolling my eyes.

[hernan_perez_br]

Re: Acer AL2416 AL2416W 24" 1920x1280 LCD Monitor

Thanks Severach, I did not realise that some caps are darker. I have ordered 10 phillips FC caps and I will replace them.
I have never changed caps before, but I think I should be able to changed it. I have a soldering iron but I have no solder.
What kind of solder should I buy?
Thank you very much!

[PlainBill]

Re: Acer AL2416 AL2416W 24" 1920x1280 LCD Monitor

Thanks Severach, I did not realise that some caps are darker. I have ordered 10 phillips FC caps and I will replace them.
I have never changed caps before, but I think I should be able to changed it. I have a soldering iron but I have no solder.
What kind of solder should I buy?
Thank you very much!

I use Kester "44" rosin core 63/37 .025" diameter. Any equivalent solder designed for electronics use will do the job. Don't use plumber's solder.

PlainBill

[hernan_perez_br]

Re: Acer AL2416 AL2416W 24" 1920x1280 LCD Monitor

Hi Guys, I have the new 100uf 35v capacitors, they are a bit bigger than the current ones but still fit in the inverter board.
Do you have any tips to desolder the current ones, I do not have a solder suck ,so I can melt the solder with my 25w iron but I can not remove the capacitor?
Are these capacitors Through-hole or surface mount? i can not see any solder in the back of the inverter board. Sorry about these basic questions but I have never sold capacitors before.
Thank you very much.
Hernan

[Toasty]

Re: Acer AL2416 AL2416W 24" 1920x1280 LCD Monitor

Surface. Just bend the leads on the new ones to match the old. 25w iron should be good enough. But, it isn't good enough for through hole components with lead-free solder.

Solder - 63/37 as PlainBill said, or 60/40 if that's all you can get.

Should not need a solder sucker for these. Carefully cut them free from the glue. Heat each leg at the board until the solder liquefies, then gently twist the cap to lift the leg. If it seems stuck, you may not have applied enough heat. Whatever you do, do not force it or you will tear the solder pad off the board.

Once you replace them, test the unit to see if the problem is corrected. If yes, then re-secure the caps like the originals. Use any decent brand of silicone adhesive/sealant.

If it's not fixed, then post back so we can continue to diagnose the problem. Leave the caps un-glued.

Toast

[hernan_perez_br]

Re: Acer AL2416 AL2416W 24" 1920x1280 LCD Monitor

Thank you Toasy, I will try twisting the cap to lift the leg. I have tried heating just one of the leg first and then the other one, but it could not lift the leg.
I will try heating both legs at the same time and twist the capacitor to lift both legs.
Then I should bend the leads on the new ones to match the old and solder them using the existing solder plus new one.
I will try it today.
Is there any tutorial to desolder surface mounted capacitors?
Thank you very much!.