Acer AL2416 AL2416W 24" 1920x1280 LCD Monitor

[wenter]

Re: Acer AL2416 AL2416W 24" 1920x1280 LCD Monitor

Do you think I should replace both fuses?

[warrior]

Re: Acer AL2416 AL2416W 24" 1920x1280 LCD Monitor

hernan_perez_br, I am having exact similar symptoms as you with my Acer AL2416W. Just curious if you were able to resolve yours and how? thanks.

[tgeml]

Re: Acer AL2416 AL2416W 24" 1920x1280 LCD Monitor

Figured Id Share my story as well,

I'm having the traditional power on/off problems related to components on the Inverter board, being fairly knowledgeable and having a great hakko 936/desoldering equipment, I removed my inverter to find the 4 north caps(C34-38) not domed, but leaking electrolytic fluid from the bottom, all the other caps looked fine.

I desoldered the caps and ordered a kit of 4 Nichicon Low ESR caps(100 Microfarad/35v) from ebay, from a guy in my state none the less, waiting for the caps atm, we'll see how my luck fairs. I found the quality of the soldering on this inverter shockingly horrible, including the excess of solder, such low quality... Here are a few images of my pogress/work.

Caps I ordered.
http://cgi.ebay.com/ws/eBayISAPI.dll...m=250661760963

Board


Leaking Caps


De-soldered Caps


Good Caps

[retiredcaps]

Re: Acer AL2416 AL2416W 24" 1920x1280 LCD Monitor

Caps I ordered.
http://cgi.ebay.com/ws/eBayISAPI.dll...m=250661760963

I wonder if the ebay seller "severach" is the same person who is on this forum? If yes, you should have no problems with his caps.

BTW, we prefer pictures hosted here using the manage attachment function and not posted inline.

[tgeml]

Re: Acer AL2416 AL2416W 24" 1920x1280 LCD Monitor

I'll fix my above post in 30 minutes, sorry! new here, haha.

[severach]

Re: Acer AL2416 AL2416W 24" 1920x1280 LCD Monitor

I wonder if the ebay seller "severach" is the same person who is on this forum?

Oh no! Caught with my hand in the cookie jar!

These Nichicon PJ 100uf 35v 8x12 caps have a larger diameter than the originals so they will not have the same polished fit as the originals. They are also a bit longer so the leads will need to be tight against the body to keep the tops away from the transformers. With some care they will all fit and they work very well. Plan how they will fit before soldering.

I couldn't find any 100uf 35v in the original NkCon 6.5x8.5 size. The only thing close I could find was a Nichicon PM 100uf 25v 6.5x15 which line up well but are very long. When I see the great size disparity between the no brand and the good brand I wonder just how good the specs were on the no brand.

[wenter]

Re: Acer AL2416 AL2416W 24" 1920x1280 LCD Monitor

My monitor is back to life!!!!!!

I have replaced 10 capacitors, 4 FET's and a fuse. And it all works

Thank you guys for your help

[Lumberjack777]

Re: Acer AL2416 AL2416W 24" 1920x1280 LCD Monitor

Which MOSFETs you folks been using to replace the p5504edg and the p2804bdg? I saw mention of FDD6690 and FDD6685, do these look viable?

"replace the p5504edg and the p2804bdg"
I second this question. I've seen 5 different suggestions out here, and in other forums. Is there a FET substitute expert out there that knows for sure. And the parts could be ordered from digikey? Thanks in advance!

[tgeml]

Re: Acer AL2416 AL2416W 24" 1920x1280 LCD Monitor

updated pics.

[Lumberjack777]

Re: Acer AL2416 AL2416W 24" 1920x1280 LCD Monitor

For the repair record.

1. Replaced the top bank of capacitors on that inverter board.

2. Replaced one small smd fuse marked W that I took from an old board.

3. Replaced the (2) P5504EDG with an FDD6685 (part # FDD6685CT-ND from Digikey) $1.20 each

4. Replaced the (2) P2804BDG with an FDD6690 (part # FDD6690ACT-ND from Digikey) $1.23 each

Total cost. About 7 bucks. Picture looks great
Thanks to all you folks out here that help so many. Retiredcaps. PlainBill. And the others.

[tgeml]

Re: Acer AL2416 AL2416W 24" 1920x1280 LCD Monitor

Progress! I got my order from sev (He sent me 2 extra caps!) I also ordered 4 of the same from digikey, so I was able to replace all 10 caps. Once replacing them, the monitor powers up, but the left side is dim, is this indicating i should replace the mosfets? I Added a high res picture of the inverter as repaired so far, if you could give me your expert opinion that would be great! thanks so much for your help this far.

[jetadm123]

Re: Acer AL2416 AL2416W 24" 1920x1280 LCD Monitor

Try checking fuses F3 and F4?, to the left of connector CN1. Also, check for the correct polarity of the caps you installed and your make sure your solder joints are not shorting out.

[jetadm123]

Re: Acer AL2416 AL2416W 24" 1920x1280 LCD Monitor

Thinking about it, check ALL the fuses on the inverter board as I'm not sure which fuse feeds what.

[tgeml]

Re: Acer AL2416 AL2416W 24" 1920x1280 LCD Monitor

All of the Fuses test ok (Continuity), polarities of the caps match up to the silkscreen, I took a magnifying glass to the section of the fets that were near the leaking caps and they look like they have a slight "Melted" look just poking out of the sides, like they melted internally. I'm just going to go ahead and order 2x FDD6685, 2x FDD6690, and 3x SF-1206F400-2CT-ND. Just gonna replace it all for good measure so I don't have to open this thing again.

[Lumberjack777]

Re: Acer AL2416 AL2416W 24" 1920x1280 LCD Monitor

I'm just going to go ahead and order 2x FDD6685, 2x FDD6690, and 3x SF-1206F400-2CT-ND. Just gonna replace it all for good measure so I don't have to open this thing again.

You probably don't need to order the fuses if they tested good. Most likely you have a shorted mosfet. Those SMD Fets are a bit tricky to unsolder. If a person isn't careful they can rip the copper trace. Here's what I did to make the job a little easier.

1. Clip the 2 legs with some really sharp wire cutters. You don't want dull ones or jiggle it in any way, because that can rip the trace. Now they desolder easily.

2. Now, on the tops I used solder wick and held the iron sideways a little to really get some heat on it. There's solder on the backside of those fets. As the solder wick starts to suck up the solder on the top. Press down a little on the iron and it should transfer the heat to the underside. With a good hot iron it should melt the solder on the backside, and it will slide off.

3. Suck up the excess solder with the wick and get the traces nice and flat again. Then I used alcohol to clean off any rosin or oils.

4. You need to lightly tin the backsides of the fets before you install them. They have a white coating on the back, and the solder just flows. Use as little solder as possible. Just to barely coat the back.

5. Position the fets to give a little gap on top for the top solder connection. Then just solder the legs. And the top. You don't have to melt the solder on the back. In fact excessive heat will kill a fet. Just solder the edge on top.

6. Take your time and have fun.

L J 7

P.S. The only reason I typed out those tips was because I ripped the copper trace on a similar board once. And it was %$#%&*^ to fix it

[tgeml]

Re: Acer AL2416 AL2416W 24" 1920x1280 LCD Monitor

Thanks for the tips, I'll be sure to be really careful! tonight i compared the fets from the side that had good caps, to the side that didnt. The fets on the bad cap side have continuity between any legs, and the back side, so im assuming they are shorted out, makes sense. The side with the good caps the fets tested good, but ill still replace em to keep matched fets.

Thanks again! I'm hoping my Hakko 936 and my desoldering pump help ease the desoldering.

[severach]

Re: Acer AL2416 AL2416W 24" 1920x1280 LCD Monitor

TO-252 (small) and TO-263 (large) SMD MOSFETs are easy with a hot air gun and a 50W iron. Flux the tab. Apply the iron to the tab. Heat is moving fast when the solder attaches to the tab through the flux. Heat the two terminals with the air gun. With experience you'll know how much to do of each and where to cheat to heat the part the least amount. The part will move as the solder on each pad releases. Use the hot air gun and iron to pick or push the MOSFET off the pads. This takes about 15 seconds if the board is warm and about 7 seconds if the board is hot.

If you had original MOSFETs you could just install them without worry. Different parts change how the circuit works and can run a lot hotter. All of the replacements I've tried run from a little hotter to so much hotter that I remove them. When you get those FETs in, run them with the back off to compare how hot they get to the originals. I'd like to find an efficient replacement MOSFET pair that is available in the USA.

[tgeml]

Re: Acer AL2416 AL2416W 24" 1920x1280 LCD Monitor

Will do, I have a Raytek Infared Minitemp to take accurate readings with too, I'll take some readings on the original fets while powered on after 5 mins, as well as the replacements.

[Curt Palme]

Re: Acer AL2416 AL2416W 24" 1920x1280 LCD Monitor

I wanted to add something here that I haven't read in this thread. I too have a couple of Acer 2416 that come on for the ACER logo, then the backlight went dead.

I checked all the caps with an ESR tester, with one leg lifted off the PC board. (I'm a board level tech, and know my way around these units.)

What I found with some experimentation is that the backlight would only come on for under a second with all 6 connected, but would stay on for about 2 seconds if I disconnected any 2 out of the 6. This indicated that the backlight shut down under full load, but since I could disconnect any of the 2 backlights, I figured that the transformers and CCFLs were OK.

I read this whole thread (well, to page 6), and kept coming back to the caps even though they checked OK. So... not expecting anything, I changed 4 of the caps. Presto, bingo, the unit works. (Yes, I'm changing the other 6 caps).

So... first order of business is CHANGE THOSE CAPS, even if they check OK. I"m about to throw them on my Sencore cap tester to see what the exact nature of the failure is of these caps.

Thought this might help others.

[Curt Palme]

Re: Acer AL2416 AL2416W 24" 1920x1280 LCD Monitor

Oh, and the caps are not bulged in any way.

The problem was the cap value. Completely out of circuit, they still read perfect ESR, but two of the caps were at 61 uF and 12uF. Go figure.