Hello. I have an old 17" LCD monitor here, NEC LCD1760NX, model: L172EN. I was trying to fix it, mostly for fun and experience, but it turned out to be more difficult than I expected.
The monitor will turn on with a fully white screen and then slowly fade to black over a 3-5 minute period. The white screen has some faint vertical lines. Nothing resembling a video signal is seen.
I did not check the electrolytic capacitors directly. Instead, I probed the power supplies with an oscilloscope. The main +5 volt and +15 volt supplies look good, very little ripple. The backlight seems to work. The 3-terminal regulators on the logic board output nice stable voltages. The ribbon cable has LVDS data going across it.
I moved over to the T-con board and found the following voltages. Vcc = 3.36, Vcom = 4.22, VGL = -5.12, VDD = 9.95, VGH = 27.4. I don't know what voltages are reasonable for driving the LCD.
I saw a recent thread on BadCaps titled "Samsung Synchmaster 2693HM WHITE SCREEN." Someone had a similar sounding problem, but no resolution yet.
Anyone have any ideas for this NEC monitor? Any ideas for more things I could test? Its pretty old and might not be worth it, but I like a challenge. Thanks for replies.
The monitor will turn on with a fully white screen and then slowly fade to black over a 3-5 minute period. The white screen has some faint vertical lines. Nothing resembling a video signal is seen.
I did not check the electrolytic capacitors directly. Instead, I probed the power supplies with an oscilloscope. The main +5 volt and +15 volt supplies look good, very little ripple. The backlight seems to work. The 3-terminal regulators on the logic board output nice stable voltages. The ribbon cable has LVDS data going across it.
I moved over to the T-con board and found the following voltages. Vcc = 3.36, Vcom = 4.22, VGL = -5.12, VDD = 9.95, VGH = 27.4. I don't know what voltages are reasonable for driving the LCD.
I saw a recent thread on BadCaps titled "Samsung Synchmaster 2693HM WHITE SCREEN." Someone had a similar sounding problem, but no resolution yet.
Anyone have any ideas for this NEC monitor? Any ideas for more things I could test? Its pretty old and might not be worth it, but I like a challenge. Thanks for replies.
Attached Files
But today, I’m making an exception here. Why? No idea. Perhaps only because the repair details are still “fresh” in my head… which is ironic, given this is a 16 year old monitor that hardly anyone will care about today. It is new to me, though. 
I picked it up last November from someone on my local Craigslist. It wasn’t very close to where I live, but was close to a family friend that I had to go visit anyways. So after watching the posting on Craigslist for a few weeks and seeing it getting...
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