ACER AL2423W - no display

[PlainBill]

Re: ACER AL2423W - no display

Here are 4 pictures of my power board. I started with changing to those green caps...

Ouch!!! The solder joints on the largest transformer look very bad. Is that an artifact of the lighting or the camera, or is that the problem?

PlainBill

[freddyfena]

Re: ACER AL2423W - no display

Here are 4 pictures of my power board. I started with changing to those green caps...

[dondrusco]

Re: ACER AL2423W - no display

Dismount aluminium shielding and post pictures (front/back) of power board.

[freddyfena]

Re: ACER AL2423W - no display

Too bad, thanks for your try. Anyone else have the possibility to get a circuit diagram? Or have some hint?

[pedro]

Re: ACER AL2423W - no display

Does that monitor have TWELVE inverter transformers? I'm looking at a SM that is purportedly for the AL2423W and it shows a board with 12 transformers, six lamp harness connectors.

Does this pic look like your unit?

Turns out this Service Manual only has schematics for the "main board", not the power board. Forget I spoke.

[pedro]

Re: ACER AL2423W - no display

replace all other crap brands while you are at it.
not sure about those hitano caps.

Hitano are the brand of choice in my repairs - up there with Panasonic and Nichicon in reliability, and readily available here.

[pedro]

Re: ACER AL2423W - no display

Does that monitor have TWELVE inverter transformers? I'm looking at a SM that is purportedly for the AL2423W and it shows a board with 12 transformers, six lamp harness connectors.

Does this pic look like your unit?

[freddyfena]

Re: ACER AL2423W - no display

Thanks so far, I have measured a bit on the primary side but can only conclude that the 230 V is being rectified to 330 V pretty soon. Before T2 there is only 330 V DC and after there is nothing, no DC no AC, i would expect 19V and 12V.
(Before T2 there is 110 V AC and 330 V/1000V DC and it is giving correctly 5V.)
So my conclusion is that there might be some component before T1 that is damaged. Does anyone have a circuit diagram for the FSP112-3F01?

[dondrusco]

Re: ACER AL2423W - no display

0 Ohms - it is OK - because it is coil.
See this thread
https://www.badcaps.net/forum/showthread.php?t=9872
there are some hints how-to check primary side components.

[freddyfena]

Re: ACER AL2423W - no display

I have measured the resistance and it's 0 ohm everywhere on the secondary side of the transformer. It was only DC, no AC on primary side. How do I see if the pulse generator has failed? Even though I have order a power board via Ebay (cheaper than Donberg) I'm still interested in finding out what really failed here.

[dondrusco]

Re: ACER AL2423W - no display

There might be problem with pulse generator for primary side of transformer. 330V doesn't mean anything - 330V is DC, but there must be AC for generating magnetic field of transformer. Measure resistance primary/secondary wiring of transformer.
You might help me with another AOC monitor - the same symptoms. No DC at secondary side.

There is (maybe) easier way to repair - to buy new power board
http://www.donberg.ie/descript/f/fsp112-3f01.htm

[freddyfena]

Re: ACER AL2423W - no display

Hi
I have now changed a bunch of bad cap but I still don't get any +12V och +19V :-(. 5V is OK
So I continued my fail search and discovered that the transformer had like 330 V in but nothing out, and at least something seems to be short circuited on the secondary side. So my problem is now how do I get a SPI 8TI00214 03 FC HI-POT 0617 GP GH-130?? I have given up goggling it now. Anyone has an idea? Else my last resort is to buy the whole power card of course.

[dondrusco]

Re: ACER AL2423W - no display

I'm not sure, but there are three feedback optoelements.
But probably yes - one for +5 and +12V and one for +19V

[kc8adu]

Re: ACER AL2423W - no display

looks like it has afpc and 2 seperate supplies.
one for +5 and +12 and the other for +19 for the inverter?

Your English is more than adequate.

I believe you are correct. The area around the 19 Volt rectifier looks very unhealthy. This is also a very interesting design; I have never seen one of these with THREE transformers, and three smps controllers.

I've marked up the top view of the power board. Check the value of the two resistors circled in red. They appear to be discolored, and could be the cause of the overheating. I have circled 5 capacitors in blue. One or two of those filters the supply for the 19V / 12V SMPS controller. If those are bad it MIGHT cause the problem you are seeing. And it is also possible the 19Volt rectifier (also circled in red) is defective. You could try replacing that.

PlainBill

[crocowhile]

Re: ACER AL2423W - no display

Caps arrived today in the mail (digi-key); I replaced CS10-16 although only three were clearly bulged. $5 and I am back in business! Worked like a charm (at least so it seems, till now; let's keep fingers crossed). Thanks folks.

[dondrusco]

Re: ACER AL2423W - no display

Don't worry, that two CS14 and CS15 have other manufacturer (TEAPO?). I had CapXon there. But it worths to replace, when you are in.

[crocowhile]

Re: ACER AL2423W - no display

That CS13 is bulged downside - CS16 might be bad,too (the same voltage/capacitance).
I highly recommend to replace CS14 and CS15. They could fail in short time (see start of this thread).

I have ordered replacements for CS10-13 and CS16 right after writing the post. Now that you mentioned it, I should have ordered 14 and 15 too :/

[dondrusco]

Re: ACER AL2423W - no display

That CS13 is bulged downside - CS16 might be bad,too (the same voltage/capacitance).
I highly recommend to replace CS14 and CS15. They could fail in short time (see start of this thread).

[sofTest]

Re: ACER AL2423W - no display

Hello everybody.
My Acer X241W is suffering of something that I believe could be related to bad cap. I can switch the monitor on and get nice image but after a few seconds the screen would turn black (no image, no blacklight). Only way to get back to image is switch off then on, but after few seconds same problem.

The monitor uses the same PSU described on this thread (FSP112 3F01) and I believe I could find at least two caps that look bulged to me ( CS11 and CS12 both 25V 650uF). There is a third cap that looks different from all the other, CS13 - 25V 100uF). The top looks ok but the cap is actually higher from the ground and there is something that looks like black rubber underneath. Is that to be replaced too? What do you think?

I am attaching two pics. Thanks!

Yes, replace the three caps you mentioned, they are all bad. I would have replaced CS10 as well. It's the same brand and model as the others, and if it's not bad now, it will be shortly.

[crocowhile]

Re: ACER AL2423W - no display

Hello everybody.
My Acer X241W is suffering of something that I believe could be related to bad cap. I can switch the monitor on and get nice image but after a few seconds the screen would turn black (no image, no blacklight). Only way to get back to image is switch off then on, but after few seconds same problem.

The monitor uses the same PSU described on this thread (FSP112 3F01) and I believe I could find at least two caps that look bulged to me ( CS11 and CS12 both 25V 650uF). There is a third cap that looks different from all the other, CS13 - 25V 100uF). The top looks ok but the cap is actually higher from the ground and there is something that looks like black rubber underneath. Is that to be replaced too? What do you think?

I am attaching two pics. Thanks!