Re: Lenovo ThinkVision L2440pwC stays black
Thanks to all for your input! The screen is fine again.
I disassembled it completely and found out that the connection between the cable and the hissing CCFL was loose (see pics attached to this post). So I removed the old solder and resoldered the connection (and also the connection to the other CCFL right next to the one that was loose).
The original insulation was a silicone part (in the pics: the white block) which I guess was molded around the joints between the cable and the CCFLs. It was damaged while I...
Neon
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Last Activity: 03-24-2021, 12:34 PM
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Re: Lenovo ThinkVision L2440pwC stays black
Ok, after a few days of tinkering with this monitor whenever I found some spare time, here are the results:
I did what retiredcaps suggested. While measuring the voltages on the connector on the power board, I noticed that the screen was on again. Happily, I reassembled the screen, just to find out it did not want to turn on again after reassembling.
So I disassembled it again and applied some contact cleaner spray on said connector. Our electronics guy has also resoldered several joints on the power board. ...Leave a comment:
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Re: Lenovo ThinkVision L2440pwC stays black
Thanks for the fast reply. You were right, Q107 and Q108 are MOSFETs. They are model P609 by Alpha & Omega (datasheet: )
I checked them in-circuit according to your MOSFET guide in [URL="https://www.badcaps.net/forum/showpost.php?p=203724&postcount=19"]post #19[/URL] using two different multimeters.
All connections you asked me to test are high-resistance (one multimeter shows them as overload, the other one shows them between 2 and 8 Megaohms). So I guess they are fine.
...Leave a comment:
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Lenovo ThinkVision L2440pwC stays black
Hallo!
I am trying to repair a Lenovo ThinkVision L2440pwC, manufactured in September 2008.
[U]Problem[/U]
The monitor worked flawlessly until last Friday, when in the morning it didn't light up.
Now, when powering on the monitor, the display stays black (so it's not a "2secs to black" problem, it rather does not light up at all) and the power LED stays on. The picture is visible when shining light on it.
[U]Things tried[/U]
I disassembled the monitor and looked for broken/burned/leaked parts... -
Re: Iiyama Prolite E481S goes dark after 1 second, blue power LED steady on
I don't mind you cheating :-)
Thanks for the photo advice. Though I hope the screen will live on for a long time...Leave a comment:
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Re: Iiyama Prolite E481S goes dark after 1 second, blue power LED steady on
It's back to life! The slightly cracked solder joint on L201 was the problem, I resoldered it (pic attached) and now the screen works fine again!
Thanks a lot alexanna for finding it and pointing it out to me! And thanks to all other helpers, too!...Leave a comment:
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Re: Iiyama Prolite E481S goes dark after 1 second, blue power LED steady on
Using the DMMs continuity checker on the four diodes in circuit I did not get any continuity. Should I run further checks on them out of circuit? Thanks for your help.Leave a comment:
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Re: Iiyama Prolite E481S goes dark after 1 second, blue power LED steady on
Both inverters are marked
80LL19T-1-DN 1
DARFON 423
I can't locate a datasheet of any "80LL19T" on the internet.
What I've found is [URL="ftp://aoc-europe.com/Products/Phased%20Out/TFT/2007/TFT%20LM960_LM965/Certificates/CB/62512TRFSAF.pdf"]this PDF[/URL] containing the info in the attached picture #2, and a person from Poland who managed to get a replacement (though [URL="http://translate.google.com/translate?hl=en&sl=pl&tl=en&u=http%3A%2F%2Fwww.elektroda.pl%2Frtvforum%2Ftopic1633251.html%237927777"]his...Leave a comment:
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Re: Iiyama Prolite E481S goes dark after 1 second, blue power LED steady on
Heres what I measured:
On TP1:
8-1: Overload
8-2: Overload
8-3: Overload
8-4: Overload
8-5: Overload
8-6: Overload
8-7: 196 ohms
On TP2:
8-1: 3.94 kilo ohms
8-2: 1.245 kilo ohms
8-3: 1.245 kilo ohms
8-4: 1.243 kilo ohms
8-5: 1.242 kilo ohms
8-6: 3.90 kilo ohms
8-7: 198 ohmsLeave a comment:
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Re: Iiyama Prolite E481S goes dark after 1 second, blue power LED steady on
Thanks for the explanation.
I measured the resistance between pin 8 and 9 of TP1: 0 (zero) ohms. Same for TP2.
Just to make sure my DMM is working, I checked a resistor of known resistance (510 ohms) from my collection, and the DMM works fine.
What does that mean?
BTW I managed to ask ************* for the removal of the oversized pics. This thread should be much easier to read now.Leave a comment:
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Re: Iiyama Prolite E481S goes dark after 1 second, blue power LED steady on
Attached: Photos after I changed the two capacitors and the four transistors....Leave a comment:
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Re: Iiyama Prolite E481S goes dark after 1 second, blue power LED steady on
Thanks for this good idea, momaka!
I've now tried to delete the pictures from imageshack, but on that site deleting is only possible if I had made an account and uploaded them using the account.
Could a mod please simply delete the IMG links from my original post? This way it is not too much work for you, and we can continue to use this thread.
I will post the photos of "before", meaning before I started changing parts on the mainboard, in this reply....Leave a comment:
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Re: Iiyama Prolite E481S goes dark after 1 second, blue power LED steady on
Thanks for your answer. I have spent the last 30 minutes searching for the "Edit" button in this board, because I read the "Posting images" FAQ --after-- opening my thread and realized my mistake.
Since I cannot edit my post (can't find the Edit button), I am stuck. Could anybody please tell me where the button is/should be, or could a mod delete the pictures from my original post so that I can post a reply with the images as attachments?
Edit: OK, it seems editing...Leave a comment:
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Iiyama Prolite E481S goes dark after 1 second, blue power LED steady on
Hi!
I have an Iiyama ProLite E481S (Model name PLE481S-S1S) flat screen connected to my laptop using a VGA cable. The screen has been working fine for 3 years. Now it fails.
Everytime I switch the flat screen on, it goes dark after a second. The power LED, however, stays on (constantly blue, not flashing) all the time.
This posting contains 12 MB of photos to give you as much (zoomable) information as possible. Please wait for them to load and resize automatically (somehow they start loading in fullsize to be resized after a few seconds) to make your reading...
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