This LCD monitor was given to me by my instructor coz' it's lying around in in their attic and was an old model. Since I have no monitor (CMV CT-934D defective main supply regulator) I was very happy to have it but the only problem was when I turned on the power the backlight flash momentarily then black out but the power LED stayed on(green). When I shone flashlight in the screen I could see the icons which means the display is fine and the backlight is defective. Anyone could help me please.
-
-
Re: A Poor Student Needs Help - NEC L70S No Backlight
Sounds like 2 second to black. See posts #19 and 20 at
https://www.badcaps.net/forum/showthread.php?t=10419
2 seconds to black can be (in no particular order)
a) bad caps
b) bad inverter transformer
c) bad ccfls
d) bad ccfl wiring (especially the return wire)Last edited by retiredcaps; 01-04-2012, 01:48 AM.--- begin sig file ---
If you are new to this forum, we can help a lot more if you please post clear focused pictures (max resolution 2000x2000 and 2MB) of your boards using the manage attachments button so they are hosted here. Information and picture clarity compositions should look like this post.
We respectfully ask that you make some time and effort to read some of the guides available for basic troubleshooting. After you have read through them, then ask clarification questions or report your findings.
Please do not post inline and offsite as they slow down the loading of pages.
--- end sig file --- -
Re: A Poor Student Needs Help - NEC L70S No Backlight
Thanks a lot. I will read and follow the instruction in troubleshooting this monitor. Do you have any schematic diagram on CMV CT-934D monitor coz' the PSU components were burned...Here's the attachments...I got the pictures here in this site since it's very similar to the PSU board. And since I have no hd camera to take the pictures.Attached FilesLast edited by apostar; 01-04-2012, 02:33 AM.Comment
-
-
Re: A Poor Student Needs Help - NEC L70S No Backlight
Pictures of a similar supply really do not help. Would you turn in a paper written by one of your classmates because 'it was similar to one you would have written'? Even an identical power supply would not have the problem that yours has.
PlainBillFor a number of reasons, both health and personal, I will no longer be active on this board. Any PMs asking for assistance will be ignored.
Never be afraid to try something new. Remember, amateurs built the ark. Professionals built the Titanic.Comment
-
--- begin sig file ---
If you are new to this forum, we can help a lot more if you please post clear focused pictures (max resolution 2000x2000 and 2MB) of your boards using the manage attachments button so they are hosted here. Information and picture clarity compositions should look like this post.
We respectfully ask that you make some time and effort to read some of the guides available for basic troubleshooting. After you have read through them, then ask clarification questions or report your findings.
Please do not post inline and offsite as they slow down the loading of pages.
--- end sig file ---Comment
-
Re: A Poor Student Needs Help - NEC L70S No Backlight
My current camera is a 4 Megapixel Olympus D-580. And that is more camera than is necessary - I have to reduce the pictures before uploading. They are now available (used) on eBay for as little as $19 with free shipping.
PlainBillFor a number of reasons, both health and personal, I will no longer be active on this board. Any PMs asking for assistance will be ignored.
Never be afraid to try something new. Remember, amateurs built the ark. Professionals built the Titanic.Comment
-
this tv is throwing me for a loop. do samsung tvs no longer have the backlight self test feature built into the power supply?
i tested the backlight with my LED tester and it lights up both strips. one of them reads 100v and the other reads 63.7v.
unplugged mainboard from power supply but left backlight plugged in, and then plugged psu wall power in. expected to see backlights light up but see nothing.
according to how ive diagnosed in the past, this would almost always be a bad power supply. replacement power supply was cheap like 20$ from ebay. but still i get not even... -
I bought this p2210f dell monitor to fix. Schematic is the same as p2210.
Behaviour is that monitors comes on but then backlight switches off almost instantly. If I look with flashlight I can still find the "No signal message". So definitely a backlight issue. Trying to advance the issue I proved that the protection circuit is switching off the backlight by shorting out C3 and resistor to disable the INL chip then re enable by removing the short.
This is where it gets interesting. When I disassembled the monitor to solder leads on c3 capacitor I noticed the backlight flickered... -
Hello all,
Am trying to figure out this backlight issue with this A1990 Macbook Pro.
Tests performed:
There is no backlight even with a good screen.
Backlight IC is receiving the correct support voltages.
Fuse F8400 ok
Current sense resistor R8400 ok
Backlight IC is receiving 3.3V on enable pin.
Backlight IC receiving voltage from PPBUS_G3H, aprox 12.5V.
Backlight IC receiving 5V from PP5V_G3S
Backlight IC BKLT_SCL and BKLT_SDA both measure 0.545V diode mode to ground
I2C_BKLT_SCL and I2C_BKLT_SDA both measure... -
Hello, got an iPad Pro A2378 12.9 5th gen with no backlight. Got another test unit without screen, tested the screen, still no backlight with the test unit.
Figured out the backlight on the screen was bad, ordred a new backlight from mobilesentrix, *carefully replaced it* without damaging the lcd, oh well.
Final result, issue is still there, the screen has no back lights. So i'm back to square one, with 3 hours less and 100$ out, issue still on the screen.
The panel is still ok, i can see the apple in the middle of the screen when it kicks in, just no backlight.
Anyone... -
Hi all,
I've got an LG Flatron 24EN33TA with a backlight issue. The problem began with the monitor not powering up after sitting for a long time (overnight or during the day throughout work). When I would wake the computer up, the backlight would flick on for a second then go out. Sometimes it would take many tries to get it to come on. Once the monitor came on, it worked flawlessly until another long duration of being powered off.
I thought the problem would be bad caps but I checked both of the caps on the board and they are fine. I also tried powering the monitor from...
Comment