View Full Version : Dell LCD monitor fixed
TerrySmith 08-03-2011, 11:31 AM Yesterday I was selling some scrap aluminum at a recycle center and found this Dell 17" LCD monitor on top of a pile of BPC TV's. I asked how much and he said ehh, you can have it!
As usual, found two blown caps, replaced them and it works! These things are not meant to be repaired as they are really cheaply made. So far I have 0 dollars invested, just a little time.
http://i147.photobucket.com/albums/r314/corvair65/MVC-045F-1.jpg
http://i147.photobucket.com/albums/r314/corvair65/MVC-046F.jpg
http://i147.photobucket.com/albums/r314/corvair65/MVC-047F.jpg
ctc17 08-03-2011, 12:25 PM Good fix! Anytime I work on any modern electronics I start with a good visual inspection of the caps. Seems to the problem about 50% of the time.
I like your ntsc background image....want.
matt_s78mn 08-03-2011, 12:34 PM let me guess... 1000uF, 10V. Pretty much every dead Dell LCD monitor I've seen has those two vented caps. Make sure your replacements have a better temperature rating and I usually replace with 25V or 35V.
TerrySmith 08-03-2011, 12:39 PM Yep, 1000uf@10v. Replaced with 1000uf@16v I scrounged from the pile-o-circuit boards I have!
Username1 08-03-2011, 01:04 PM I always check out the recycled tvs at our recycling center. But this year seems like they only get 20 sets to a truckload. I can't remember seeing stuff that big in the stores.... Everything seems to be giant tube sets, and cube projection sets. They put one on a skid, and thats it. I wonder how many of those sets work, and how many only need a its bitsy 39 cent cap......
bandersen 08-03-2011, 01:09 PM Nice job! I was about to toss a couple Samsung LCD monitors because I assumed the CFL backlights were dying.
Luckily, someone tipped me off about the bad caps. Sure enough - I replace a few bulging caps and they work like new :)
Reece 08-03-2011, 01:16 PM I did the same with an HP monitor and went in with caps rated somewhat better than the originals. They were a little bigger and had to lie on their sides to fit in the cramped quarters.
ChrisW6ATV 08-03-2011, 07:28 PM Good work! I like the newer electrolytics with the vent lines on top because they are easier to identify when they are bad compared to using an ESR meter.
compucat 08-03-2011, 08:10 PM I repaired a 19" HP LCD monitor that was dead by replacing three bulging electrolytic caps. As mentioned by another member I had to lay them on their sides to fit in the cramped cabinet. The monitor works like new and is in daily service. I got it free and only spent a few dollars for caps. It is great to be able to fix an otherwise good monitor without having to throw it away.
freakaftr8 08-04-2011, 04:36 PM Congrats on the LCD monitor fix! You will also find those 1000mfd 10v caps failing in Samsung and Magnavox plasma TV's as well causing a failure code flashing on the power led. Yep gotta love cheap taiwan cap espoinage.
Hemingray 08-05-2011, 04:32 PM e172FPb? Watch out on those, another common problem (as one I have has experienced), is the driver transistors for the backlights will short out. (this will cause a blinking green power light)
wa2ise 08-07-2011, 08:40 PM Some bad cap adventures for me here: My brother found a "Digix media DV288" DVD player in the trash at his condo. A "Fuhjyyu" brand 1000uF 10V cap vented, and made the player inoperative. Replaced it, and it works now. Also changed out the other caps of this brand. Also found a "ground loop" style problem, switching power supply crud was getting into the video output. Must have been that way since day 1. Was able to correct that by disconnecting the chassis ground from the power supply ground.
Of course the remote is missing. Limited functionality without it.
Hemingray 08-09-2011, 03:16 AM A "Fuhjyyu" brand 1000uF 10V cap vented, and made the player inoperative.
Typical. Fuhjyyu's are complete junk. They're mostly intolerable to heat.
mbates14 08-10-2011, 11:16 PM Just to throw an oddball out there for you guys, I have repaired a couple of these same dells with a newer-style power supply, same monitor though. Had better capacitors.
However, the CCFLs have failed. Usually can spot those by hearing a bad hiss from the inverter and instant shutdown (with good caps).
swapping the CCFLs with new ones worked like a charm. just worked a deal out with a chinese supplier, as i needed 8 of them and at $7 bucks a peice that gets expensive. I will say that disassembling the panel is a royal pain in the ass syndrome.
I have done some other weird things, like bolting a 37" toshiba chassis that had a broken screen, onto a scrap but good 42" Olevia-LG LCD panel, Both had the same LVDS connection. and built a wooden frame. It worked. LOL makes a good shop TV/monitor, only thing I had to do was some rewiring for the inverters, as i used the original inverters on the Olevia panel. The PWM/enable signals come through the T-con on the Olevia panel, They came straight from the signal board on the original toshiba setup. and surprisingly the firmware knew how to autosense and control it via the T-con.
all i did was rewire the power supply connection wires to fit the toshiba power supply.
Usually, if the programmers are smart, they take advantage of the ID code stored into the panel's T-con module. When requested, the panel replies with an ID code that contains the panel type, resolution, etc... and better written firmware will auto sense and switch modes to support the connected panel. Laptops do this, the video BIOS knows how to handle that.
Toshiba chassis did, philips you have to modify the option codes in system service menu.
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