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Old 10-26-2010, 02:49 PM   #21
dt2rz
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Default Re: Acer AL2416 AL2416W 24" 1920x1280 LCD Monitor

It looks domed in that picture but actually there are no domed caps on any of the boards. Sorry, camera is not so good.
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Old 10-26-2010, 03:11 PM   #22
mathog
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Default Re: Acer AL2416 AL2416W 24" 1920x1280 LCD Monitor

Quote:
Originally Posted by dt2rz View Post
It looks domed in that picture but actually there are no domed caps on any of the boards.
If the electrolytic caps in the secondary part of the power supply are any of the known bad brands replace them anyway. (Unless you have an ESR tester and can verify that they are within specification in situ.)

Also, if you have a known good CCFL with the same type connectors use it to replace the tubes in your monitor one by one. Specifically, plug that tube from the "good" display board into the socket on your inverter board, and leave the corresponding "test" lead on your Acer board hanging loose. (Don't take the panels apart and swap the tubes, at least, not yet!) All it takes is one CCFL that is too old to cause these symptoms. Unless you are very unlucky only one tube will have aged that far, so by systematically replacing all of them you can eliminate that possibility. or identify the bad tube.

Last edited by mathog; 10-26-2010 at 03:15 PM..
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Old 10-26-2010, 03:58 PM   #23
dt2rz
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Default Re: Acer AL2416 AL2416W 24" 1920x1280 LCD Monitor

Power board is fitted with rubycon caps. I don't have any spare items (CCFL)

to test further. I borrowed a DMM from a friend of mine and I wanted to test

the power board outputs. How can I go about testing for the power outputs?
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Old 10-26-2010, 05:13 PM   #24
mathog
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Default Re: Acer AL2416 AL2416W 24" 1920x1280 LCD Monitor

Rubycon is one of the better brands. Even so, read the numbers off the cans and look up the specs for this particular set. Or post the numbers here.

Before you do anything else you need to verify that +5 and +12V on the power supply board are good. There may be some test points available, for instance, the legs of the capacitors, if you can reach them. If not, there are some unused through holes on the power supply board. If you follow the traces on the back you can probably find empty pads that are at ground (definitely) and +5 and +12V (probably). Solder bits of wire to the pads on the back, through the holes, to bring the voltage points to the top of the board, then you can put the DIMM on those after you wire everything back together like it was in your first posted picture, but without the power supply shield. The +12V supply may not be regulated all that well but should be >= 12V (it could be 13, for instance). The +5V should be very close to 5V. This will only be in the few seconds from turn on until the screen blanks. After that these voltages will drop.

It would really help if you could scrounge up one more good CCFL somewhere. You can waste a lot of time trying to debug the electronics when they are working properly and a bad CCFL is at fault. Also, there are 6 CCFLs in that display, so more chances to go wrong. If any one of those 6 is bad you would see what you see. Some people have been successful with the cheap CCFL light kits from Fry's and elsewhere (around $10). In both directions, testing the CCFL tubes with the light kit inverter, and testing the inverter with the light kit CCFL tube. Problem is, the kit sockets never match up with those in the LCD display. If you want to spend real money, lcdparts.net has a couple of inverter testers, one is around $100 and the other $37. I do not know how well they work since I have never used either one.
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Old 10-29-2010, 11:43 AM   #25
babiloof
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Question Re: Acer AL2416 AL2416W 24" 1920x1280 LCD Monitor

Hi everyone! :> This forum is awesome, helpded me alot...

Anyway I also have this monitor, and i would like your advise...
First the backlight didnt work then i replaced 4 caps that looked to be faulty.
Then the backlight worked but the left side of the screen is darker and i can hear a noise :o

Quote:
Originally Posted by bonney View Post
If Q5 and Q6 are weak they give you half brightness on the left side same if you dont use P5504EDG P2804BDG
Should i replace them ?
Should i replace any other caps ?
Maby the backlight is broken ?
Attached Images
File Type: jpg P1100987.JPG (213.5 KB, 183 views)
File Type: jpg P1100989.JPG (39.6 KB, 135 views)
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Old 10-29-2010, 11:52 AM   #26
bonney
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Default Re: Acer AL2416 AL2416W 24" 1920x1280 LCD Monitor

Hi change all 10 caps first
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Old 10-29-2010, 04:01 PM   #27
dt2rz
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Default Re: Acer AL2416 AL2416W 24" 1920x1280 LCD Monitor

Quote:
Originally Posted by bonney View Post
Hi change all 10 caps first
This is where i'm at right now. Just waiting for the caps i ordered from Digi-key and give it a try.
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Old 10-29-2010, 10:05 PM   #28
gybruss
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Default Re: Acer AL2416 AL2416W 24" 1920x1280 LCD Monitor

Quote:
Originally Posted by bonney View Post
Acer AL2416W
Inverter TDK P/N TBD292LF
10 capacitors 100uf 35v miniature
Fuse F2 marking M
Q4 faulty P2804BDG
Q6 can go faulty P5504EDG
Q3 faulty P2804BDG
Q5 can go faulty P5504EDG
Hi, i replace the 10 caps, found f1 is blown, witch of the Q do i need to replace?

Can anyone tell me where to buy these parts?
thanks
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Old 10-30-2010, 03:03 AM   #29
bonney
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Default Re: Acer AL2416 AL2416W 24" 1920x1280 LCD Monitor

You need to replace Q3,Q4 Niko-Sem P2804BDG Q5,Q6 Niko-Sem P2804BDG and the fuse
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Old 10-30-2010, 07:00 AM   #30
gybruss
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Thumbs up Re: Acer AL2416 AL2416W 24" 1920x1280 LCD Monitor

Quote:
Originally Posted by bonney View Post
You need to replace Q3,Q4 Niko-Sem P2804BDG Q5,Q6 Niko-Sem P2804BDG and the fuse
Thanks, bonney,
juste to be clear , you said the same part numer for all the 4Q's on the last reply? Is there a part number for the fuse? noobee here on ordering parts, and i need a store where to order the part, i live in canada, so a canadian site if you happen to know one?
thanks
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Old 10-30-2010, 07:27 AM   #31
bonney
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Default Re: Acer AL2416 AL2416W 24" 1920x1280 LCD Monitor

Yes my mistake
Q5,Q6 Niko-Sem P5504EDG
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Old 10-30-2010, 07:26 PM   #32
dt2rz
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Default Re: Acer AL2416 AL2416W 24" 1920x1280 LCD Monitor

Replaced the following parts on the inverter board:

-10 caps with 100uf 25v 85*c 2000 hour Chemicon SMG

-Q3 & Q4 with FDD6690, i can't find original P2804BDG

-Q5 & Q6 with FDD6685, i can't find original P5504EDG

Result is still the same. I tried checking the CCFLs one by one and all are

lighting up fine. Can somebody guide me in testing the power supply. Here

are some more pics of the power supply...
Attached Images
File Type: jpg acer24in 012.jpg (876.7 KB, 141 views)
File Type: jpg acer24in 014.jpg (1.05 MB, 100 views)
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Old 10-31-2010, 04:23 AM   #33
bonney
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Default Re: Acer AL2416 AL2416W 24" 1920x1280 LCD Monitor

on your inverter there are two fuses have you power to them ?
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Old 10-31-2010, 04:46 AM   #34
bonney
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Default Re: Acer AL2416 AL2416W 24" 1920x1280 LCD Monitor

PIN NO. Function Function
1 +24Vcc Inverter Vcc
2 +24Vcc Inverter Vcc
3 +24Vcc Inverter Vcc
4 +24Vcc Inverter Vcc
5 +24Vcc Inverter Vcc
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
Backlight On/Off control signal, connected to CNS1#11
13 Dimmer Brightness control, connected to CN1#12,bright
max.=3.3V,min.=0V.
14 N.C N.C

they are the connectors to your inverter
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Old 10-31-2010, 01:21 PM   #35
dt2rz
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Default Re: Acer AL2416 AL2416W 24" 1920x1280 LCD Monitor

Thanks bonney! The 2 fuse on the inverter board are ok. I'll post results after

checking.
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Old 10-31-2010, 02:34 PM   #36
dt2rz
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Default Re: Acer AL2416 AL2416W 24" 1920x1280 LCD Monitor

Here are the results i got:

1 +24Vcc Inverter Vcc ====== 23.9V
2 +24Vcc Inverter Vcc ====== 23.9V
3 +24Vcc Inverter Vcc ====== 23.9V
4 +24Vcc Inverter Vcc ====== 23.9V
5 +24Vcc Inverter Vcc ======= 23.9V
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 ====== 2.7V
13 Dimmer Brightness control ====== 2.5V
14 N.C N.C


Here's for the logic board:
1 +5Vstb ======= 5V
2 GND
3 GND
4 GND
5 +5Vcc ======= 5V
6 +5Vcc ======= 5V
7 +5Vcc ======= 5V
8 +12Vcc {audio power (n/a option)}
9 GND
10 Power on ======= 2.7V
11 Backlight on/off ======= 2.7V
12 Dimmer ======= 2.5V
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Old 10-31-2010, 03:17 PM   #37
bonney
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Default Re: Acer AL2416 AL2416W 24" 1920x1280 LCD Monitor

I'm not sure a like your transistor's double check the data sheets
have you tested the old ones?
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Old 10-31-2010, 03:33 PM   #38
dt2rz
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Default Re: Acer AL2416 AL2416W 24" 1920x1280 LCD Monitor

Quote:
Originally Posted by bonney View Post
I'm not sure a like your transistor's double check the data sheets
have you tested the old ones?
No i can't because i burnt the transistors while removing them from the board

with the soldering iron. Nothing changed with the issue after replacing the parts

so maybe the problem is somewhere else?

Last edited by dt2rz; 10-31-2010 at 03:39 PM..
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Old 10-31-2010, 03:48 PM   #39
bonney
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Default Re: Acer AL2416 AL2416W 24" 1920x1280 LCD Monitor

looks like you have to go to ebay
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Old 10-31-2010, 03:52 PM   #40
dt2rz
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Default Re: Acer AL2416 AL2416W 24" 1920x1280 LCD Monitor

Yeah i guess that's the next hard step, finding expensive discontinued parts

Thanks for trying to help though.
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