U2312HM backlight turns off

Hi rrlagic,

Dell U3014 Monitor provides a self-test feature that allows you to check whether your monitor is functioning properly. Here are the steps:

• Turn Off both your computer and the monitor.
• Unplug the video cable from the back of the computer. To ensure proper Self-Test operation, remove all video cables from the back of computer.
• Turn on the monitor.
• The floating dialog box should appear on-screen (against a black background) if the monitor cannot sense a video signal and is working correctly. While in self-test mode, the power LED remains white.
• Depending upon the selected input, one of the dialogs shown below will continuously scroll through the screen.
  
   
  
   
  
  
  
  
  
  
  
• This box also appears during normal system operation if the video cable becomes disconnected or damaged.
• Turn Off your monitor and reconnect the video cable; then turn On both your computer and the monitor.

If your monitor screen remains blank after you use the previous procedure, check your video controller and computer, because your monitor is functioning properly.

You may also perform Built-in Diagnostics to determine if the screen abnormality you are experiencing is an inherent problem with your monitor, or with your computer and video card. Here are the steps:

• Ensure that the screen is clean (no dust particles on the surface of the screen).
• Unplug the video cable(s) from the back of the computer or monitor. The monitor then goes into the self-test mode.
• Press and hold the 'Button 1' and 'Button 4' on the front panel simultaneously for 2 seconds. A gray screen appears.
• Carefully inspect the screen for abnormalities.
• Press the 'Button 4' on the front panel again. The color of the screen changes to red.
• Inspect the display for any abnormalities.
• Repeat steps 5 and 6 to inspect the display in gray, red, green, blue, black, white, and text screens.
• The test is complete when the white screen appears. To exit, press the 'Button 4' again.

Note: You can run the built-in diagnostics only when the video cable is unplugged and the monitor is in 'self-test mode'.

If you do not detect any screen abnormalities upon using the built-in diagnostic tool, the monitor is functioning properly. Check the video card and computer.

Hope this helps. Please reply if you have any questions.

Self test seems to be passed. However, I found a more reliable way to reproduce the problem. If I change display resolution and apply settings, very often backlight goes off. With this trouble returned to the seller for diagnostic.

Hi rrlagic,

If I understand you correctly, have you returned the monitor to the seller for testing purpose?

If not please try resetting the monitor back to factory defaults. Here are the steps:

• Open the OSD Menu.
• Navigate to Other Settings --> Factory Reset --> Reset All Settings.
• Check the functionality.

Note: Factory Reset will erase any of your saved custom display settings.

Please reply with the information.

Hello,

The seller's technician confirmed that trouble exists. However, they told me that authorized engineer has to evaluate my monitor to make decision. Anyway, I have no monitor at the moment. As to reset to factory setting, I did not modify anything except brightness.

Hi rrlagic,

Thank you for the information. Please keep me posted with the results. Also, if you need any assistance from my end, let me know. I'll be glad to help.

Hi rrlagic,

Glad to know that the monitor is replaced and issue is resolved. Do reach out if you need any assistance, I'll be happy to help.

I've got new notebook and doc station as well, and my U2312HM started exhibit weird behaviour just as in initial post: losing backlight on UAC prompt, not resuming after standby. The radical fix was to use display port instead of DVI. Yes, I had to purchase another cable, but that finally solved my issue with the second monitor.

You might want to try a different video cable, or at least disconnecting and reconnecting the one you have. I actually have this exact same monitor and mine doesn't exhibit this behavior.

As a work-around, you can disable power-save mode for the monitor in the power options control panel.

If require more help, please let me know.

Regards,

Purvi Jain