Acer AL2416 AL2416W 24" 1920x1280 LCD Monitor

[yohnsee]

Re: Acer AL2416 AL2416W 24" 1920x1280 LCD Monitor

A little update on the topic.
I successfully brought this gem back to life, and it is working since 4 weeks.
And it has an amazing picture! I read about it, this was some kind state-of-art back then, but on a simple VGA input it makes so vivid and perfect picture. Most of today's screens can't reach this level. So I am very satisfied with it.

[yohnsee]

Re: Acer AL2416 AL2416W 24" 1920x1280 LCD Monitor

I read different posts in which they used 1.25A fast fuse but lately one user reported it blown again.
I would use a 2A fast littlefuse.

Thank you. I got myself into it, and read back nearly all the posts. Accordig to them, I would probably need a 4A fast acting type. I ordered a few from ebay. In case they would be too much (4A) and the smoke came out, I will not worry, because I am repairing this for my own use, so as soon as something goes hairy, I will hit the breaker on my desk

[Dumah Brazorf]

Re: Acer AL2416 AL2416W 24" 1920x1280 LCD Monitor

I read different posts in which they used 1.25A fast fuse but lately one user reported it blown again.
I would use a 2A fast littlefuse.

[yohnsee]

Bought this gem for buttons, looking forward to repair it

Hello everyone, I see this is an old thread, but I was thinking I may add some new info.
So I bought this unit cheap and knowing it is faulty, my first approach was to take it apart. (BTW, I LOVE taking things apart )
Monitor was showing no backlight, but hooked it up to my pc, picture was OK with the flashlight test.
With the help of this thread, I managed to filter out the possibly bad parts.
On the inverter board, the 4 caps that are the closest to Q4, Q6 Mosfets are bulged and have a significantly darker color. Q4 and Q6 are showing 10 ohms in every direction and F2 is open. In the first round, I replace all the 10 caps on the inverter board, Q4 and Q6 also. I have already ordered the replacement parts. It will take some time to get to me, but I am not in a hurry.
I read most of the replies here, has anyone figured out the value for the F2? Only a "M" is printed on its top, nothing to be found on the internet.
Update will come, as soon the bad parts are replaced.
Cheers

[bartolo]

Re: Acer AL2416 AL2416W 24" 1920x1280 LCD Monitor

i´m new in this board and have find many usefull hints.
thanks to all.

but after replacing several caps in my AL2416 i also sticked a heatsink on the processor ic of the logic board and now the monitor runs and runs....

bartolo

sorry for my bad english!

[jche]

Re: Acer AL2416 AL2416W 24" 1920x1280 LCD Monitor

The fuse is there for a reason. If you didn't have that fuse, then you'd probably have a bit of smoke and some burned out mosfets.

Thanks for the response - I understand fuses are there for a reason and was just asking which part of the circuit this particular one is protecting and from what kind of damage - looks like in your opinion I'm only risking frying some mosfets which I wouldn't call the end for the world. The thing is that while I'm looking for the replacement (not very hard) the monitor has been working in a full time office setting for a few days now with no smoke..

[jetadm123]

Re: Acer AL2416 AL2416W 24" 1920x1280 LCD Monitor

My question is: since I did not have the replacement for the fuse I just soldered in a piece of wire in it's place - what risk am I running by using the monitor without that fuse? Can anything major fry?

The fuse is there for a reason. If you didn't have that fuse, then you'd probably have a bit of smoke and some burned out mosfets.

[jche]

Re: Acer AL2416 AL2416W 24" 1920x1280 LCD Monitor

I have fixed 4 or 5 of these so far with a pretty minimal knowledge about electronics. Most of the times it was the was the inverter board and just the 4 caps on the top of the board (C34,35,36 & 38.) On the last one though after the replacing of the caps didn't help I also replaced the mosfet right next to the caps (Q6), which looked a little singed - no luck. In the end it turned out that one additional culprit was the F2 fuse.

My question is: since I did not have the replacement for the fuse I just soldered in a piece of wire in it's place - what risk am I running by using the monitor without that fuse? Can anything major fry?

[Chyenne]

Re: Acer AL2416 AL2416W 24" 1920x1280 LCD Monitor

Hi,
a night later I just tried again. Got past the acer logo, showed the desktop and shut off two seconds later, but still normal buzzing from the power board. Not accepting button input:

To inverter board:
1 +24Vcc Inverter Vcc ====== 23.8V
2 +24Vcc Inverter Vcc ====== 23.8V
3 +24Vcc Inverter Vcc ====== 23.8V
4 +24Vcc Inverter Vcc ====== 23.8V
5 +24Vcc Inverter Vcc ======= 23.8V
6 GND Inverter GND
7 GND Inverter GND
8 GND Inverter GND
9 GND Inverter GND
10 GND Inverter GND
11 N.C N.C
12 Backlight on/off ====== 2.1V
13 Dimmer Brightness control ====== 2.1V
14 N.C N.C


To main board:
1 +5Vstb ======= 5.1V
2 GND
3 GND
4 GND
5 +5Vcc ======= 5.1V
6 +5Vcc ======= 5.1V
7 +5Vcc ======= 5.1V
8 +12Vcc {audio power (n/a option)}
9 GND
10 Power on ======= 2.3V
11 Backlight on/off ======= 2.3V
12 Dimmer ======= 2.1V

Then did a power cycle. Everything dead again, except:

To main board:
1 +5Vstb ======= 5.1V

Thanks again.

[budm]

Re: Acer AL2416 AL2416W 24" 1920x1280 LCD Monitor

OK, the PS_ON is working because it does change state when monitor is turn on and off, but the BL_ON (Backlights on/off) is not working because it stays at 0V.
The BL_ON is generated by the main board, so that is where we have to look next.
Pictures of your main board?

[Chyenne]

Re: Acer AL2416 AL2416W 24" 1920x1280 LCD Monitor

Ok, I think I misunderstood you the first time.
After it rested for a little over an hour I plugged everything in (the led turned on, no backlight, no picture, not able to turn it off) and measured again:

To inverter board:
1 +24Vcc Inverter Vcc ====== 23.8V
2 +24Vcc Inverter Vcc ====== 23.8V
3 +24Vcc Inverter Vcc ====== 23.8V
4 +24Vcc Inverter Vcc ====== 23.8V
5 +24Vcc Inverter Vcc ======= 23.8V
6 GND Inverter GND
7 GND Inverter GND
8 GND Inverter GND
9 GND Inverter GND
10 GND Inverter GND
11 N.C N.C
12 Backlight on/off ====== 0V
13 Dimmer Brightness control ====== 0V
14 N.C N.C


To logic board:
1 +5Vstb ======= 5.1V
2 GND
3 GND
4 GND
5 +5Vcc ======= 5.1V
6 +5Vcc ======= 5.1V
7 +5Vcc ======= 5.1V
8 +12Vcc {audio power (n/a option)}
9 GND
10 Power on ======= 2.3V
11 Backlight on/off ======= 0V
12 Dimmer ======= 2.3V

I then cut the power, powered it up and it's dead again (no led, backlight, picture, unable to turn it on) and measured:

To inverter board:
1 +24Vcc Inverter Vcc ====== 0V
2 +24Vcc Inverter Vcc ====== 0V
3 +24Vcc Inverter Vcc ====== 0V
4 +24Vcc Inverter Vcc ====== 0V
5 +24Vcc Inverter Vcc ======= 0V
6 GND Inverter GND
7 GND Inverter GND
8 GND Inverter GND
9 GND Inverter GND
10 GND Inverter GND
11 N.C N.C
12 Backlight on/off ====== 0V
13 Dimmer Brightness control ====== 0V
14 N.C N.C


To logic board:
1 +5Vstb ======= 5.1V
2 GND
3 GND
4 GND
5 +5Vcc ======= 0.3V
6 +5Vcc ======= 0.3V
7 +5Vcc ======= 0.3V
8 +12Vcc {audio power (n/a option)}
9 GND
10 Power on ======= 0V
11 Backlight on/off ======= 0V
12 Dimmer ======= 0V

[budm]

Re: Acer AL2416 AL2416W 24" 1920x1280 LCD Monitor

"10 Power on ======= 0V" The main board is not sending the PS_ON to turn on the 24V and 5V power supply.

[Chyenne]

Re: Acer AL2416 AL2416W 24" 1920x1280 LCD Monitor

Thanks for replying so fast. I just hooked up everything and now it's completely dead. The pc detects the monitor but it doesn't react at all. The fuse on the power board is still good, as is the bridge rectifier... If I measure the big cap immediately after disconnecting power I'll catch it at over 200V (if that helps).

[budm]

Re: Acer AL2416 AL2416W 24" 1920x1280 LCD Monitor

Is it connected to running PC?

[Chyenne]

Re: Acer AL2416 AL2416W 24" 1920x1280 LCD Monitor

Hi,
I was not sure if I should open a new thread or not, but I will try here.
Two years ago I got this monitor working again (thanks to this thread) by replacing the 10 caps and a mosfet on the inverter board, but this time the symptoms are different.
After running for a few hours it turned off and on again by itself, once. Now, if I connect the power cord, it turns on by itself, shows the logo for 2 seconds, then the logo highlights red or it shows a weird small menu item for a fraction of a second and the monitor turns off (no amber led light, no image under flashlight).
As far as I can tell the mosfets on the inverter are not shorted and the fuses are fine.
Testing the power board with everything disconnected I get the following:
(post for reference: https://www.badcaps.net/forum/showpo...5&postcount=36)

To inverter board:
1 +24Vcc Inverter Vcc ====== 0V
2 +24Vcc Inverter Vcc ====== 0V
3 +24Vcc Inverter Vcc ====== 0V
4 +24Vcc Inverter Vcc ====== 0V
5 +24Vcc Inverter Vcc ======= 0V
6 GND Inverter GND
7 GND Inverter GND
8 GND Inverter GND
9 GND Inverter GND
10 GND Inverter GND
11 N.C N.C
12 Backlight on/off ====== 1.8V
13 Dimmer Brightness control ====== 0V
14 N.C N.C


To logic board:
1 +5Vstb ======= 5.1V
2 GND
3 GND
4 GND
5 +5Vcc ======= 0.01V
6 +5Vcc ======= 0.01V
7 +5Vcc ======= 0V
8 +12Vcc {audio power (n/a option)}
9 GND
10 Power on ======= 0V
11 Backlight on/off ======= 2.1V
12 Dimmer ======= 0V

Since my cheap DMM only goes to 250V I can not test across the big cap. I`m at a loss at this point.
Thank you.

[re-atari]

Re: Acer AL2416 AL2416W 24" 1920x1280 LCD Monitor

I'll check the rating of the fuses on the inverter board. I recall they were 3A, so 1,25A is definitely too light. I will check just to make sure.

re-atari

I checked my own info about the repair actions on my 2416's, and found out I used 1,5A fuses in a resistor type casing. The wires on each end made it quite easy to fit them. I didn't solder them to the original smd pads though, instead just followed the traces on the PCB and soldered the wires to the respective components.

I haven't been able to find the photo's I took back then. Since it looks like your 2416 is resurrected, I think this is not a very urgent matter?

I would advise to use the monitor without its back shell in place for the first few days, and check whether the FETs are running hot. If the shield on the inverter is too hot to touch, the caps and FETs will definitely not last long. Using 85 degree caps may cause the FETs to run too hot. Do check if you used 105 degree types, and if that's not the case, replace the caps asap.

re-atari

[budm]

Re: Acer AL2416 AL2416W 24" 1920x1280 LCD Monitor

So does the LED sray amber, as youi can see in my pictures, it should be green.
Also if the caps are bad, it will have lots of high frequency feeding the inverter circuits and causes it to draw lots of current.
https://www.badcaps.net/forum/showth...416#post288703
More pictures here:
http://s807.photobucket.com/user/bud...62548698263046

http://s807.photobucket.com/user/bud...77036580452451

[re-atari]

Re: Acer AL2416 AL2416W 24" 1920x1280 LCD Monitor

Allright,

I gave one last shot at my original board. Since I was sure the fuse was blown, I replaced it and voila! The monitor is back to life.

So the inverter board from eBay was likely faulty. So the question now is what the right value for the fuse? I saw people saying it was 'W', others were saying 'M'. I got a 'J' surface mount fuse, rated at 1.25A. Not sure how long the new fuse will hold. Crossing fingers.

That's really good news, another monitor saved from the landfill

I'll check the rating of the fuses on the inverter board. I recall they were 3A, so 1,25A is definitely too light. I will check just to make sure.

re-atari

[re-atari]

Re: Acer AL2416 AL2416W 24" 1920x1280 LCD Monitor

I thought about this and tried connecting only one half of the circuit with no luck.

As a test you could try running the monitor fully assembled, but with all connectors to the backlight lamps disconnected. Check if you can faintly see an image on the entire screen with a flashlight. If that's the case, the fault lies with the replacement inverter. If it's not, I'm more or less clueless. Any further investigation will require testing voltages with a multimeter for starters.
My instinct tells me it's the PSU, but that's way to small a basis to go out and buy a replacement PSU... I'll check the photo's I made of my PSU and videoboard again for possible suspect caps. I'm not too keen on opening up my 2416's again.

I already attempted a repair on the original board, and it lasted about 2 weeks at 8~10 hours/day until it failed again. I didn't investigate the root cause this time; the fuse is blown up again (I actually verified that) but i am unsure about the FETs or the capacitors. I thought it would be easier to just go ahead and get a replacement board altogether, but it looks like even this is a risky business.

Yes, I misread your earlier posts, thought you wrote the replacement board worked for 2 weeks. I only later on realised you actually said it was the repair that failed
If the fuse has gone again, one or more of the FETs on its side of the inverter will be shot as well. Test both FETs for shorts wih your multimeter. Did you after your repair by any chance check if they ran hot?
The 10 caps on the board do really need to be low ESR (105 degrees), standard types (85 degrees) will either not work at all or fail quickly with possibly expensive collateral damage. Chances are that's what happened with your repair...

I'll think about what to do next... Maybe I'll just bite the bullet and purchase a new monitor; this one served me well for many years and it lacks a display port connector/controler.

I know what you mean, both my 2416's only have a VGA port, not even DVI although the traces are present on the PCB. I already figured how to retrofit a DVI port and even acquired the necessary components, but in the end did not go through with this project. The SMD's were just too small to handle, let alone solder them in correctly.
So I just left it at that and donated the monitors to each of the kids, to see the smiles on their faces was priceless

re-atari

[sle118]

Re: Acer AL2416 AL2416W 24" 1920x1280 LCD Monitor

Allright,

I gave one last shot at my original board. Since I was sure the fuse was blown, I replaced it and voila! The monitor is back to life.

So the inverter board from eBay was likely faulty. So the question now is what the right value for the fuse? I saw people saying it was 'W', others were saying 'M'. I got a 'J' surface mount fuse, rated at 1.25A. Not sure how long the new fuse will hold. Crossing fingers.