AL1916W: backlight goes deed after 5s

[raisdfist]

Re: AL1916W: backlight goes deed after 5s

Well it seems i have also a problem with this type of LCD. With a small diference. My monitor starts up, displays the acer logo, goes blank for 3-4 seconds, and then the box where it should display green signal apears, 2-3 seconds and the monitor goes in standby, without any of the front panels working. In the box, the text is not displayed, and no command button is working at any time. My guess is that i have a corrupted eprom or processor, but my question is, do i have any chance to write it again, or i should start looking for another board. I post a few photos, if any questions please ask, and if i need to make any measurements, please point them an the photo because i am not an native english speaker, and you know what it sayes, a picture is worth as a 1000 words .

You have a different board than the one I have, it is similar to the one I have in the one I repaired, so I sugess that you check continuity on fuse F200 on the green side of the board.

if the pictures does not work here is the link
good luck

[Wizard]

Re: AL1916W: backlight goes deed after 5s

The letter on this SMD is a fuse current rating to blow at that limit.

Make sure lamp inverter & lamps are not the issue. Had this monitor still attached to the running PC and power LED stayed green (so to speak)?

Corrupt eeprom is only for user setting stored. Trick is change EEPROM for another EEPROM from any scrapped board that has similar IC or larger than this. (this is only a 8 pin IC SMD on the mainboard (usually 24Cxx) etched into this IC body. The microcontroller will put in default user settings in the EEPROM on power up.

Cheers, Wizard

[Wizard]

Re: AL1916W: backlight goes deed after 5s

Corrupt eeprom is only for user setting stored. Trick is change EEPROM for another EEPROM from any scrapped board that has similar IC or larger than this. (this is only a 8 pin IC SMD on the mainboard (usually 24Cxx) etched into this IC body. The microcontroller will put in default user settings in the EEPROM on power up.

Fuse: There is no "M" and this letter is really "W" which is 4A. Make sure you have no shorted transistor somewhere if so, better get another board.

Cheers, Wizard

[PlainBill]

Re: AL1916W: backlight goes deed after 5s

One additional point. Sometimes the eeprom is not defective, rather the data is corrupted. Google reset monitor for information on resetting monitors. The procedure varies by brand, model, and even production run, but doesn't require any soldering, or even opening the monitor.

PlainBill

[msdos85]

Re: AL1916W: backlight goes deed after 5s

Ok, i have looked for that fuze, but i'm sure the model is not the same. I post 2 more photos of the powerboard. But i have noticed that if i connect the monitor to the computer, the acer logo displays, it goes away, but the green led stays on. I have tryed to turn aroud the monitor in all positions to see if it displays anything, but i can't see anything on him.
About the reset, i'm not sure i can do this without the buttons working .

[msdos85]

Re: AL1916W: backlight goes deed after 5s

I have also tryed to connect the monitor to my pc while the pc was on, then i plugged in the power to the monitor, it started, displayed the acer logo, goses blank, the led sayes green, i hit the reset button on the pc, the monitor lighted back and displayed the box in the second photo of my first post, and turned off, even after the pc started again, with the orange led, meaning it got in the standby. I disconnected him and connected my old monitor, and i have noticed that windows saw my acer and it changed my resolution to acers native resolution 1440*900 .

[Bookworm]

Re: AL1916W: backlight goes deed after 5s

Okay, jumping back in again - I just pulled out the Acer monitor to do some additional abuse, especially since I now have a _second_ identical monitor with identical failure problems.

I've resoldered the transformers, just in case, as well as ran some voltage tests. The resistance is fine across the transformer. The suggested voltage test to ground from the CCFL attachment points all showed _under_ .2 volts for all points. Some were .2, some .1, and some .06 and so forth.

Quite frankly, I can't even find a surface mount fuse on this particular board (it's the original pic posted, as well as modified), so I can't test jumpering

If it is the mosfet, I haven't found any replacements, so not sure If I should junk the monitors for recycling or not.

BW

[PlainBill]

Re: AL1916W: backlight goes deed after 5s

Okay, jumping back in again - I just pulled out the Acer monitor to do some additional abuse, especially since I now have a _second_ identical monitor with identical failure problems.

I've resoldered the transformers, just in case, as well as ran some voltage tests. The resistance is fine across the transformer. The suggested voltage test to ground from the CCFL attachment points all showed _under_ .2 volts for all points. Some were .2, some .1, and some .06 and so forth.

Quite frankly, I can't even find a surface mount fuse on this particular board (it's the original pic posted, as well as modified), so I can't test jumpering

If it is the mosfet, I haven't found any replacements, so not sure If I should junk the monitors for recycling or not.

BW

Let's do this systematically, and see if we can't get it working. First of all, my instructions were wrong - or at least had a typo in them. The voltage test should be done with the meter on the AC voltage range. That may be the reason the voltage readings are too low.

PLEASE don't trash the monitors. If nothing else, offer them on Freecycle or Craigslist.

PlainBill

[Bookworm]

Re: AL1916W: backlight goes deed after 5s

I'll test it again, but the meter is autosensing. It showed sort of the same thing on both AC and DC (as I recall).

Now, one thing I _could_ do is grab one of the power supplies for a scanner CCFL, and plug it into the tubes themselves and see what happens

I'd prefer to repair them myself - i figure that there aren't many folks on craigslist/freecycle that are going to be 1) better than I am at it, and 2) willing to put the time/money into the repairs.

[Bookworm]

Re: AL1916W: backlight goes deed after 5s

Before I pull one back out and try to test voltage on pin 7, or something like that, any _detailed_ suggestions on what, remaining, to test?

BW

[PlainBill]

Re: AL1916W: backlight goes deed after 5s

Before I pull one back out and try to test voltage on pin 7, or something like that, any _detailed_ suggestions on what, remaining, to test?

BW

Well, since you consider yourself better than anyone on craigslist / freecycle, why would you need DETAILED suggestions? All a competent tech should have to do is look at the schematic and make the measurements which will identify why the controller is shutting down. Then it's only a matter of identifying the cause of the errant readings.

PlainBill

[mathog]

Re: AL1916W: backlight goes deed after 5s

I have the same board as shown in the first post in this thread. The failure mode seems to be a little different than reported by others. When turned on the screen never lights up. Instead the power light goes to green, then orange, then off, and cycles that way over about 2-3 seconds forever. The fuse is OK. There is one slightly bulging cap (c815, green on my board, all the others are black as in the posted picture, will replace all caps at some point). When it runs they all have a "reasonable" (nonzero) voltage across them, although maybe not the right voltage. The green one definitely discharges much faster than the others though. 5V to the logic board is OK, no voltage on the CCFL drive connectors. The only sign of distress is a slight brownish tinge on the board around the R816 100 Ohm resistor, the one just below the 79069140___R letters. The resistor measures what it should.

I'm up to replacing macroscopic components, but don't have the tools, or the eyes, for working on the itty bitty stuff surface mounted on the solder side of the board. Somebody linked to a manual earlier in the thread, but the part numbers don't match up with my board exactly.

Anybody know of a cheap, reliable, and easily located replacement for this card? It seems to be more of a PITA to fix than most, but doesn't seem to be doing anything really special to warrant the work. Near as I can tell it is just driving the CCFL backlight and the interface to the logic board is nothing special.

Thanks.

[mathog]

Re: AL1916W: backlight goes deed after 5s

I repaired this one many months ago but forgot to post the details. On the board there were the following electrolytic capacitors (not counting the big one), sizes are approximate:

C501,C817 470uF 25V Su'scon [10mm x 18mm]
C815 1000uF 25V Su'scon [13mm x 20mm]
C818 1000uF 10V Samxon (?) [10mm x 16mm]
C820,C827,C807 47uF 25V Samxon [6mm x 13mm]

Of these only C818 was swollen.

Replaced all of those on the list with Panasonic FM and it came right up. My son has been using it (for too many hours each day) for four months and it hasn't had any further problems.

[Recycler]

Re: AL1916W: backlight goes deed after 5s

Sorry to dig this up, but I wanted to report the tip supplied by magistertc worked in my case. It was explained here:

https://www.badcaps.net/forum/showpost.php?p=81234&postcount=58

Acer 1916W. Same problem.
This monitor has the same OZ9938GN. I found the OVP on pin 7 of IC501 to be 1.2 volts, and vsense would rise to 1.7 volts and the backlight was shut down.
The solution was to put a 1M resistor 1/8w between pin 2 (vdd) and pin 7 (OVP)
OVP is now at 2.1 volts and the backlight stays on.

Ofcourse this is cheating, but in my country it is impossible to get the transformers and the lamps are way to expensive.
So this will give the monitor some extra time.

Cheers.

[budm]

Re: AL1916W: backlight goes deed after 5s

That means the MOSFET is drawing too much current due to bad transformers/lamps, it will be just a matter of time before either the MOSFET gives out or the transformer/lamps will completely burn out. But do what you have to do when you have no choice.

[compassion1122]

Re: AL1916W: backlight goes deed after 5s

I have a similar problem same model but 06; Acer appears in the dark and so does the web page. I can see the menu and tried to brighten but to no avail. probably happened during one of our lightening storms but it is plugged into a surge protector hmm. have held power button down flickers a light for a second but I can see my post that I am typing but the screen is dark hmm. I have tester guess I will open it up but you all know a lot more than I but I loves a challenge to fix something. TY

[killian6pk]

Re: AL1916W: backlight goes deed after 5s

I have a similar problem same model but 06; Acer appears in the dark and so does the web page. I can see the menu and tried to brighten but to no avail. probably happened during one of our lightening storms but it is plugged into a surge protector hmm. have held power button down flickers a light for a second but I can see my post that I am typing but the screen is dark hmm. I have tester guess I will open it up but you all know a lot more than I but I loves a challenge to fix something. TY

I repaired this monitor. The reason for the shutdown in mine was the top lamp had the smaller of the two wires burnt thru. Replacing the wire repaired mine. Only problem was I broke the lamp putting it back in and had to buy a replacement. It works now. If you find that this is your problem be very careful with the lamps they are very small and fragile.

[raydem]

Re: AL1916W: backlight goes deed after 5s

So you all know that "deed" is just how the Scottish say "dead" :-P

Typical situation here -- another power board with a problem not obvious to me. This monitor is from my office and was going to the landfill, but I thought I should see if a fix is possible.

When I first tried it after it had been sitting for several months unused, it worked for 10 minutes before the backlight went off. I did notice a bit of flicker in the screen. Now, it stays on for a second or two before the backlight goes out. The image is still on the screen, just no backlight, and the power LED stays green.

See what you folks think. This is an interesting BB; it seems one can fix anything provided you have an internet connection and some basic tools ;-)

Hi, i know this post is very old, but i need help. I have the same power board (ilpi-025), but all the schematics about the AL1916W monitor are different. I need the value of the resistors R812 and R807.

Thank you