Acer AL1916W

[Jasgriff]

Well I went from having not monitors to fix to having a bunch to fix.

As a part of this bunch there are 3 of these Acer AL1916W's

All monitors were either showing signs of 2 seconds to black or not lighting up at all.

When I took the first one apart I could see that there were a few badly bloated caps and there were burn marks around one of the Mosfets. I tested the burnt one and it had definitely blown. The Inverter transformer tested ok so I am going to order 2 Mosfets ( aop605 ) to replace them both and I am going to replace all of the caps. I have tested the screens CCFL's on another power supply and they appear to be ok.

I cracked open which was suffering from 2 seconds to black and everything appeared to be ok. Caps looked ok transformer tested ok and the mosfets were not burnt and they tested ok. I tested the voltage across the Mosfets and saw that when the monitor was turned on on the Inverters are given power that the voltage across the mosfets dropped right off. I thought looking at the caps in the first monitor that there is a good chance that some of these had gone but they were not showing it. I went ahead and swapped out the 2 1000 25v caps and then tested again. The monitor fired up and worked ok however it did look like it had a little flicker which went away after being on for some time. I will order all of the caps to do the whole board just incase.

I am still testing the third monitor as it doesn't seem to be showing a fault as of yet.

[budm]

Re: Acer AL1916W

Ah, AL1916, there are at least 6 versions of this model.
When the caps do not properly filter the DC, you get a lot of high frequency AC riding on top of the DC and caused the Inverter switching frequency to be running at the wrong frequency, this will cause the Output MOSFET's to run hot and blow up, just like bad tuning caps that has gone bad..
Look like you will be busy for awhile.
http://s807.photobucket.com/albums/yy352/budm/ACER/

[retiredcaps]

Re: Acer AL1916W

Well I went from having not monitors to fix to having a bunch to fix.

Wow, good score if you didn't pay a whole lot for it or got them for free. A good opporuntity to sell them as dual monitor setup.

Bonus points again for the multimeter shots.

[Jasgriff]

Re: Acer AL1916W

@Budm I will definitely be changing all caps then. You would think that this would keep me busy for a while wouldn't you! I picked them up at 2PM and went through them all in one day. 6 are now working and I have ordered the parts for the other 6 I just need to get my front room tidy as the parts are coming from china and we know how long that takes.

@Retiredcaps I did pay for them but selling 3 of them will cover that cost. The rest I can fix for fun and then sell to fund another bunch of monitors.

[Jasgriff]

Re: Acer AL1916W

I was very tired yesterday and didn't really go into the detail of this board so here it is if any other have issues or questions regarding this model.

Capacitor List :

CE108 - Taicon 330uf 25v
C200 - Capxcon KF 220uf 25v
CE102 - Capxcon KF 1000uf 25v
CE104 - Taicon 1000uf 10v
CE109 - Capxcon KF 220uf 25v
CE103 - Capxcon KF 1000uf 25v
CE101 - Capxcon KF 220uf 25v
CE105 - Capxcon KF 2200 10v

Power Mosfet :

IC201 - AOP605
IC202 - AOP605

I will update when the rest of the bits arrive.

[tom66]

Re: Acer AL1916W

Replace CE107 too, common startup cap failure. (Just for future reliability.)

[Jasgriff]

Re: Acer AL1916W

CE107 Capxcon 22uf 50v

Will be changed too

[Jasgriff]

Re: Acer AL1916W

Ok,

I have been waiting for a few parts from China so I haven't been able to do a lot with these until now.

I have 2 of these that are faulty this one had 2 blown SMPS ic's. All of the caps on this board were blown which no doubt caused the ic's to blown.

Here are a couple of pic's of the board with the caps and IC's removed I am going to clean this up and pop on another pic with most of the components refitted.

[Jasgriff]

Re: Acer AL1916W

Right,

Fitted the new SMPS ic's and all the caps but it still would not power the back lights on at all.

I took a look on the bottom of the board and found an SMD fuse had blown. I replaced this with another one that I stole from another board and it still wouldn't work. I took the board apart and unfortunately the fuse had again blown taking with it at least 1 SMPS IC.

[retiredcaps]

Re: Acer AL1916W

I took the board apart and unfortunately the fuse had again blown taking with it at least 1 SMPS IC.

With the AOP605 mosfets removed, do the pads on the pcb show a short if you measure S1-G1, S1-D1, D1-G1, S2-G2, S2-D2, D2-G2?

[jetadm123]

Re: Acer AL1916W

Right,

Fitted the new SMPS ic's and all the caps but it still would not power the back lights on at all.

I took a look on the bottom of the board and found an SMD fuse had blown. I replaced this with another one that I stole from another board and it still wouldn't work. I took the board apart and unfortunately the fuse had again blown taking with it at least 1 SMPS IC.

Which fuse was blown?

[Jasgriff]

Re: Acer AL1916W

The blown fuse was F200 which is on the bottom of the board.

I tested the chip before I turned it on and it was definitely not shorted before hand. I will take the chip out and check the pads again and give a reading without.

I have noticed that the schottky diode which is connected to F200 is showing infinite resistance which ever way I test it. Could this have blown the IC's and the fuse?

[retiredcaps]

Re: Acer AL1916W

I have noticed that the schottky diode which is connected to F200 is showing infinite resistance which ever way I test it.

What happens if you test the diode with the diode test function on the Fluke 175?

[jetadm123]

Re: Acer AL1916W

The blown fuse was F200 which is on the bottom of the board.

I have noticed that the schottky diode which is connected to F200 is showing infinite resistance which ever way I test it. Could this have blown the IC's and the fuse?

Are you talking about diode D101?

[Jasgriff]

Re: Acer AL1916W

Yeah D101.

I will give it a test on the diode function tomorrow.

[hifihifi]

Re: Acer AL1916W

I had a totally dead AL1916W.

I found power diode D101 in short, I replaced it. Then the green light goes on, after 5 sec light turn in to orange. This is without video connected.

Backlights don't flashes, keeps black all the time.

[selldoor]

Re: Acer AL1916W

Please try it with a video source - some monitors drop straight into standby without it.

Please can you update your profile with Country and Mains Voltage.

We can help a lot more if you please post good clear pictures of the whole chassis, and then pictures of each board, front and back and close up of connectors, (max resolution 2000x2000 and 2MB) using the manage attachments button, which is found by clicking "go advanced" under quick reply.

Please do not post inline and offsite as they slow down the loading of pages.

Examples of what is needed
https://www.badcaps.net/forum/attach...1&d=1290283049

https://www.badcaps.net/forum/attach...7&d=1280167246

It will be useful if you can say a bit about yourself - skills tools etc.