ACER AL2423W - no display

[dondrusco]

Re: ACER AL2423W - no display

What about to move this 22uF capacitor away from MOS heatsink? This failure is temperature - dependent. Monitor needs to be cca 1 minute turned off to work for 5 minutes.

The Zener diode ZD270 looks bad, too. There is brown circuit board beneath. What type it is?

[Behemot]

Re: ACER AL2423W - no display

I tried Samxon GF 22 uF as previously posted, it was working for several hours but after assembly it did nto turn on at all. Display was than running for a week with original 10 uF CapXon caps…

[dondrusco]

Re: ACER AL2423W - no display

I received another Acer - AL2023.
There were real disaster inside. Both boards have bulged capacitors.
The power board 9 and main board 8.

Power board:
3x470uF/35V
2x470uF/25V
2x1000uF/16V
1x470uF/16V
1x220uF/25V

Main board
7x330uF/16V (I haven't got 330uF- i have used 470uF)
1x100uF/25V

I replaced them, and now it works.

I have another Acer AL2023 - replaced all caps except two 10uF/50V in primary circuit/feedback control.

Monitor turned off backlight after 20 minutes. Green LED stayed on.
After turn off/on monitor works for anoher 15 minutes.

I have thought, that failure is in backlight circuit .

I put it away for a day. Then I decided to check reference design of power controller ( I haven't got two 10uF/50V capacitors on me) - there is 22uF capacitor for initial voltage of CM0765R. I tried to replace 10uF with 22uF and the second one (10uF/50V), too.

Failure again, but it is typical two seconds to black... -> backlight...

[Behemot]

Re: ACER AL2423W - no display

I have Fio, I believe EUR payments to and also from Slovakia are without any fees. Or use PayPal.

Found only ultra-low ESR caps on eBay so far, but it's probably due to the fact I didn't look for low ESR yet

Well distrelec does not have much of usable caps (general purpose Chemi-Cons usually in too big casing) and their prices are terrible.

[dondrusco]

Re: ACER AL2423W - no display

I'm lazy to search in eBay - thank you for suggestion, I will do it next time.

It's pity, that Czech Republic hasn't introduced EURo - wired transfer fee is horrible. I prefer to order parts from DE or AT - no fees.

[Behemot]

Re: ACER AL2423W - no display

U can take caps from me, looks pretty much like I am only distributor of Samxon in this region now Will also take very cheap ultra-low ESR caps from eBay next time…thanks to some suggestions in next thread

[dondrusco]

Re: ACER AL2423W - no display

Prašť jak uhoď, no better option in this big Slovak village.

[Behemot]

Re: ACER AL2423W - no display

sHITANO, YAGEO, all shit…they will work for some time, bud bad caps always die. Time depends only on conditions, but they will…

Hm, teď v Praze, že by ještě staré souřadnice

[dondrusco]

Re: ACER AL2423W - no display

Zdravím Moravu!

I'm using YAGEO SX,SC series (from Avelmak.sk) or HITANO EXR (GME.sk, gme.cz) - no bulged capacitor for two years of service (cca 15 LCDs, 10 PSUs, 2 MoBos).

[Behemot]

Re: ACER AL2423W - no display

Which caps would you recommend instead of CapXons KF 10 uF/50V (120 ripple, 2 impedance)? I tried Chemi-Cons KMG, but it was not working (power supply went into safe mode almost directly). Samxon's GK 22 uF worked for ten hours, than I gave it to a guy for long run test and it went into safe mode after 10 minutes. What about GK 10 uF? According to Joe's web, they have 285 ripple, 0,03 ESR.

It is now working with the CapXons, but they are pretty close to a heatsink, I am afraid they will eventually die which cannot happen - I will have to provide warranty for the repaired displays.

[Behemot]

Re: ACER AL2423W - no display

I received another Acer - AL2023.
There were real disaster inside. Both boards have bulged capacitors.
The power board 9 and main board 8.

Power board:
3x470uF/35V
2x470uF/25V
2x1000uF/16V
1x470uF/16V
1x220uF/25V

Main board
7x330uF/16V (I haven't got 330uF- i have used 470uF)
1x100uF/25V

I replaced them, and now it works.

Got the same, after aprox. an hour image supposedly freezing, monitor displaying NO SIGNAL and after some 10 seconds continuing to run fine. But no bulging caps. Replaced them anyway, tested for 45 minutes. Have been watching it for last 20 minutes and did not notice anything strange. Will give it to a guy which will use it for couple of hours and tell me how's it doing.

I hope it will be fine, there is another 14 of this monitors, all doing the same - this could be GOLDMINE for me. Joe will be happy too, ordering Samxons when I'll run out of Chemi-Cons KY

[Milton Valentin]

Re: ACER AL2423W - no display

Thanks for the information. Can you provide Part Numbers of the CS14, CS15 and CS16 caps used on the FSP 112-3F01 Board (Monitor ACER Model No. X241W) Please. Thanks.

[doutrinador]

Re: ACER AL2423W - no display

People,

Just passing by to say thanks to everyone that already put hands on job and let us know here. I Started reading here 2 weeks ago when my X241W showed the same symptons. After that i looked to buy the correct caps.
Today me and my friend changed all the bad caps... It's seem like the same bulged caps...
My monitor was working sometimes, but i decided to open before it went dead completely. That's my tip...If your monitor is starting to show the signs, open up and do the job... Take pictures as you disassemble and change the caps with no hurry. I took 2 hours to do it all.

Guys, thanks, my Monitor works flawlessly!!!! If any one needs help, just shout!

[pedro]

Re: ACER AL2423W - no display

My issue with my Acer X241W is that when it is powered down or on standby for a period of time, there is garbage on the screen for about 5-10 minutes. After which time the display appears to be normal. As long as the system does not power down, the display works fine. If it powers down, then once powered up, the garbage is on the screen for another 5-10 minutes. Any suggestions?

Yes, start a separate thread.

[gamo62]

Re: ACER AL2423W - no display

My issue with my Acer X241W is that when it is powered down or on standby for a period of time, there is garbage on the screen for about 5-10 minutes. After which time the display appears to be normal. As long as the system does not power down, the display works fine. If it powers down, then once powered up, the garbage is on the screen for another 5-10 minutes. Any suggestions?

[CleanSC]

Re: ACER AL2423W - no display

CleanSC: I accidentally ripped the wires out of the 1x4 header for the speaker output. Could you kindly zoom in on one of your pictures around the connector? Thanks!

My monitor just died recently (same model). ACER repaired it in January 2010, and they said they replaced the Power Supply. Now it is out-of-warranty. No bulging caps. Symptoms are that when I turn the power switch on, the green LED power light goes on and out quickly. It could be some kind of power supply watchdog to ensure all rails are present (and power off if not), or something else altogether. Were you able to operate the PSU without the CPU board attached? It appears that the uppermost two pins of the interconnect pins appear to be a way for the CPU board to power the power supply off (says ON/OFF) and another says BR ADJ (?).

Thanks!

Hey Rob, sorry for the late reply; first time homeownership is no joke! I will look thru my old shots to see if I have what you need. If you can, post my initial pic with the area highlighted that you would like a zoom of.

[JustRob]

Re: ACER AL2423W - no display

On boards I have personally tested, there are usually only 2 voltages. One is 5V and the other can be 12V, 19V, or 24V depending on the design.

The 5V is for the logic. The "other" is for the inverter section. From my own testing, I usually see both voltages present (regardless of load). If one is missing, check the items I mentioned in the previous post.

So for your particular board, if you see 19V marked on the PCB, then it should be PCB (we don't have pictures of your board).

On the PCB, it shows three voltages and currents:
5V@3.5A
12V@2.0A
19V@3.5A

Interestingly, there are two traces that connect the logic board to the inverter board. The PCB is the exact same as here (multiple posts and pictures). I plan to take it apart for probing purposes but all the Metcal stuff is at work. Not that I am working on SMT parts, but they have better heat dissipation than most end-user soldering irons. Thanks for your replies!

[retiredcaps]

Re: ACER AL2423W - no display

Thanks, I just didn't know if the logic board is supposed to 'enable' the 12V section. I.e., is the 12V not being enabled, or should it power up immediately, or does the logic board, having not seen 12V, immediately shuts down (5V still present).

I see that there is a 19V section, I wonder if that is used for boost converter section for the backlight.

On boards I have personally tested, there are usually only 2 voltages. One is 5V and the other can be 12V, 19V, or 24V depending on the design.

The 5V is for the logic. The "other" is for the inverter section. From my own testing, I usually see both voltages present (regardless of load). If one is missing, check the items I mentioned in the previous post.

So for your particular board, if you see 19V marked on the PCB, then it should be PCB (we don't have pictures of your board).

[JustRob]

Re: ACER AL2423W - no display

Yes, the 12V DC is used for the inverter section. If your 12V DC is not present, it could be a number of things.

1) Bad caps. Even though the caps are not bloated, they could be out of uF or have high ESR (ohm) or dried out.

2) The 12V Schottky diode could shorted. You can measure the diode using your multimeter to see if 12V is present.

Thanks, I just didn't know if the logic board is supposed to 'enable' the 12V section. I.e., is the 12V not being enabled, or should it power up immediately, or does the logic board, having not seen 12V, immediately shuts down (5V still present).

I see that there is a 19V section, I wonder if that is used for boost converter section for the backlight.

[retiredcaps]

Re: ACER AL2423W - no display

Thanks, looks like 12V rail is dead. 5V is present (but only used for logic). I assume the 12V is used for the DC/DC fluorescent back-lighting. Can the PSU be operated safely without any load on 5V or 12V? Some PSUs are unstable in this mode, I just don't know if this is one of them!

Yes, the 12V DC is used for the inverter section. If your 12V DC is not present, it could be a number of things.

1) Bad caps. Even though the caps are not bloated, they could be out of uF or have high ESR (ohm) or dried out.

2) The 12V Schottky diode could shorted. You can measure the diode using your multimeter to see if 12V is present.

I don't know enough about this monitor to answer the PSU load question.